microblaze: Move individual board linker scripts to common script in cpu tree.

Unification for all microblaze boards.

Signed-off-by: Michal Simek <monstr@monstr.eu>
diff --git a/arch/microblaze/config.mk b/arch/microblaze/config.mk
index abea70b..aca79e2 100644
--- a/arch/microblaze/config.mk
+++ b/arch/microblaze/config.mk
@@ -29,3 +29,5 @@
 CONFIG_STANDALONE_LOAD_ADDR ?= 0x80F00000
 
 PLATFORM_CPPFLAGS += -ffixed-r31 -D__microblaze__
+
+LDSCRIPT ?= $(SRCTREE)/$(CPUDIR)/u-boot.lds