selftests/powerpc/switch_endian: Fix out-of-tree build

[ Upstream commit 266bac361d5677e61a6815bd29abeb3bdced2b07 ]

For the out-of-tree build to work we need to tell switch_endian_test
to look for check-reversed.S in $(OUTPUT).
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NSasha Levin <sashal@kernel.org>

tools/testing/selftests/powerpc/switch_endian/Makefile

@@ -8,6 +8,7 @@ EXTRA_CLEAN = $(OUTPUT)/*.o $(OUTPUT)/check-reversed.S
 top_srcdir = ../../../../..
 include ../../lib.mk
 
+$(OUTPUT)/switch_endian_test: ASFLAGS += -I $(OUTPUT)
 $(OUTPUT)/switch_endian_test: $(OUTPUT)/check-reversed.S
 
 $(OUTPUT)/check-reversed.o: $(OUTPUT)/check.o