kselftest/arm64: Make the tools/include headers available

Make the generic tools/include headers available to the arm64 selftests so
we can reduce some duplication.

Signed-off-by: Mark Brown <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Will Deacon <[e-mail]>

tools/testing/selftests/arm64/Makefile

···
 
 CFLAGS += $(KHDR_INCLUDES)
 
+CFLAGS += -I$(top_srcdir)/tools/include
+
 export CFLAGS
 export top_srcdir