efi_loader: rename Unicode collation protocol 2 variables

Rename variables to make it clear they refer to the Unicode collation
protocol identified by the EFI_UNICODE_PROTOCOL2_GUID.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
diff --git a/lib/efi_selftest/Makefile b/lib/efi_selftest/Makefile
index d0bebc7..cfbb40c 100644
--- a/lib/efi_selftest/Makefile
+++ b/lib/efi_selftest/Makefile
@@ -38,7 +38,8 @@
 efi_selftest_watchdog.o
 
 obj-$(CONFIG_EFI_DEVICE_PATH_TO_TEXT) += efi_selftest_devicepath.o
-obj-$(CONFIG_EFI_UNICODE_COLLATION_PROTOCOL) += efi_selftest_unicode_collation.o
+obj-$(CONFIG_EFI_UNICODE_COLLATION_PROTOCOL2) += \
+efi_selftest_unicode_collation.o
 
 obj-$(CONFIG_CPU_V7) += efi_selftest_unaligned.o
 obj-$(CONFIG_EFI_LOADER_HII) += efi_selftest_hii.o