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

Some of our Makefiles don't do the right thing when building the
selftests with O=, fix them up.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

tools/testing/selftests/powerpc/cache_shape/Makefile

 # SPDX-License-Identifier: GPL-2.0
 TEST_PROGS := cache_shape
 
-all: $(TEST_PROGS)
-
 $(TEST_PROGS): ../harness.c ../utils.c
 
 top_srcdir = ../../../../..

tools/testing/selftests/powerpc/ptrace/Makefile

@@ -7,8 +7,6 @@ TEST_PROGS := ptrace-gpr ptrace-tm-gpr ptrace-tm-spd-gpr \
 top_srcdir = ../../../../..
 include ../../lib.mk
 
-all: $(TEST_PROGS)
-
 CFLAGS += -m64 -I../../../../../usr/include -I../tm -mhtm -fno-pie
 
 ptrace-pkey core-pkey: child.h

tools/testing/selftests/powerpc/signal/Makefile

 # SPDX-License-Identifier: GPL-2.0
 TEST_PROGS := signal signal_tm
 
-all: $(TEST_PROGS)
-
 $(TEST_PROGS): ../harness.c ../utils.c signal.S
 
 CFLAGS += -maltivec

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