tools: selftests: fix build issue with make kselftests target

Fix the typo of ARCH when running 'make kselftests'.  Change the 'X86'
to 'x86'.  Test by compilation.
Signed-off-by: Phong Tran <tranmanphong@gmail.com>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shuah Khan <shuah.kh@samsung.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

tools/testing/selftests/ipc/Makefile

 uname_M := $(shell uname -m 2>/dev/null || echo not)
 ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/i386/)
 ifeq ($(ARCH),i386)
-        ARCH := X86
+        ARCH := x86
 	CFLAGS := -DCONFIG_X86_32 -D__i386__
 endif
 ifeq ($(ARCH),x86_64)
-	ARCH := X86
+	ARCH := x86
 	CFLAGS := -DCONFIG_X86_64 -D__x86_64__
 endif
 
 CFLAGS += -I../../../../usr/include/
 
 all:
-ifeq ($(ARCH),X86)
+ifeq ($(ARCH),x86)
 	gcc $(CFLAGS) msgque.c -o msgque_test
 else
 	echo "Not an x86 target, can't build msgque selftest"

tools/testing/selftests/kcmp/Makefile

 uname_M := $(shell uname -m 2>/dev/null || echo not)
 ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/i386/)
 ifeq ($(ARCH),i386)
-        ARCH := X86
+        ARCH := x86
 	CFLAGS := -DCONFIG_X86_32 -D__i386__
 endif
 ifeq ($(ARCH),x86_64)
-	ARCH := X86
+	ARCH := x86
 	CFLAGS := -DCONFIG_X86_64 -D__x86_64__
 endif
 
@@ -15,7 +15,7 @@ CFLAGS += -I../../../../usr/include/
 CFLAGS += -I../../../../arch/x86/include/
 
 all:
-ifeq ($(ARCH),X86)
+ifeq ($(ARCH),x86)
 	gcc $(CFLAGS) kcmp_test.c -o kcmp_test
 else
 	echo "Not an x86 target, can't build kcmp selftest"

tools/testing/selftests/memfd/Makefile

 uname_M := $(shell uname -m 2>/dev/null || echo not)
 ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/i386/)
 ifeq ($(ARCH),i386)
-	ARCH := X86
+	ARCH := x86
 endif
 ifeq ($(ARCH),x86_64)
-	ARCH := X86
+	ARCH := x86
 endif
 
 CFLAGS += -D_FILE_OFFSET_BITS=64
@@ -14,20 +14,20 @@ CFLAGS += -I../../../../include/uapi/
 CFLAGS += -I../../../../include/
 
 all:
-ifeq ($(ARCH),X86)
+ifeq ($(ARCH),x86)
 	gcc $(CFLAGS) memfd_test.c -o memfd_test
 else
 	echo "Not an x86 target, can't build memfd selftest"
 endif
 
 run_tests: all
-ifeq ($(ARCH),X86)
+ifeq ($(ARCH),x86)
 	gcc $(CFLAGS) memfd_test.c -o memfd_test
 endif
 	@./memfd_test || echo "memfd_test: [FAIL]"
 
 build_fuse:
-ifeq ($(ARCH),X86)
+ifeq ($(ARCH),x86)
 	gcc $(CFLAGS) fuse_mnt.c `pkg-config fuse --cflags --libs` -o fuse_mnt
 	gcc $(CFLAGS) fuse_test.c -o fuse_test
 else