Makefile: Fix the location of the migration file

Since commit e1910d93b890 ("doc: driver-model: Convert MIGRATION.txt to
reST") MIGRATION.txt has been converted to migration.rst, so update
the Makefile references accordingly.

Fixes: e1910d93b890 ("doc: driver-model: Convert MIGRATION.txt to reST")
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/Makefile b/Makefile
index f4de30b..10c5d06 100644
--- a/Makefile
+++ b/Makefile
@@ -983,7 +983,7 @@
 	@echo >&2 "This board does not use CONFIG_DM_MMC. Please update"
 	@echo >&2 "the board to use CONFIG_DM_MMC before the v2019.04 release."
 	@echo >&2 "Failure to update by the deadline may result in board removal."
-	@echo >&2 "See doc/driver-model/MIGRATION.txt for more info."
+	@echo >&2 "See doc/driver-model/migration.rst for more info."
 	@echo >&2 "===================================================="
 endif
 endif
@@ -993,7 +993,7 @@
 	@echo >&2 "This board does not use CONFIG_DM_USB. Please update"
 	@echo >&2 "the board to use CONFIG_DM_USB before the v2019.07 release."
 	@echo >&2 "Failure to update by the deadline may result in board removal."
-	@echo >&2 "See doc/driver-model/MIGRATION.txt for more info."
+	@echo >&2 "See doc/driver-model/migration.rst for more info."
 	@echo >&2 "===================================================="
 endif
 endif
@@ -1004,7 +1004,7 @@
 	@echo >&2 "controller driver to use CONFIG_AHCI before the v2019.07"
 	@echo >&2 "release."
 	@echo >&2 "Failure to update by the deadline may result in board removal."
-	@echo >&2 "See doc/driver-model/MIGRATION.txt for more info."
+	@echo >&2 "See doc/driver-model/migration.rst for more info."
 	@echo >&2 "===================================================="
 endif
 ifeq ($(CONFIG_LIBATA),y)
@@ -1014,7 +1014,7 @@
 	@echo >&2 "enabled. Please update the storage controller driver to use"
 	@echo >&2 "CONFIG_AHCI before the v2019.07 release."
 	@echo >&2 "Failure to update by the deadline may result in board removal."
-	@echo >&2 "See doc/driver-model/MIGRATION.txt for more info."
+	@echo >&2 "See doc/driver-model/migration.rst for more info."
 	@echo >&2 "===================================================="
 endif
 endif
@@ -1024,7 +1024,7 @@
 	@echo >&2 "This board does not use CONFIG_DM_PCI Please update"
 	@echo >&2 "the board to use CONFIG_DM_PCI before the v2019.07 release."
 	@echo >&2 "Failure to update by the deadline may result in board removal."
-	@echo >&2 "See doc/driver-model/MIGRATION.txt for more info."
+	@echo >&2 "See doc/driver-model/migration.rst for more info."
 	@echo >&2 "===================================================="
 endif
 endif
@@ -1034,7 +1034,7 @@
 	@echo >&2 "This board does not use CONFIG_DM_VIDEO Please update"
 	@echo >&2 "the board to use CONFIG_DM_VIDEO before the v2019.07 release."
 	@echo >&2 "Failure to update by the deadline may result in board removal."
-	@echo >&2 "See doc/driver-model/MIGRATION.txt for more info."
+	@echo >&2 "See doc/driver-model/migration.rst for more info."
 	@echo >&2 "===================================================="
 endif
 endif
@@ -1052,7 +1052,7 @@
 	@echo >&2 "This board does not use CONFIG_DM_SPI_FLASH. Please update"
 	@echo >&2 "the board to use CONFIG_SPI_FLASH before the v2019.07 release."
 	@echo >&2 "Failure to update by the deadline may result in board removal."
-	@echo >&2 "See doc/driver-model/MIGRATION.txt for more info."
+	@echo >&2 "See doc/driver-model/migration.rst for more info."
 	@echo >&2 "===================================================="
 endif
 endif
@@ -1063,7 +1063,7 @@
 	@echo >&2 "Please update the board to use CONFIG_WDT before the"
 	@echo >&2 "v2019.10 release."
 	@echo >&2 "Failure to update by the deadline may result in board removal."
-	@echo >&2 "See doc/driver-model/MIGRATION.txt for more info."
+	@echo >&2 "See doc/driver-model/migration.rst for more info."
 	@echo >&2 "===================================================="
 endif
 endif