uml: correctly strip kernel defines from userspace CFLAGS

KERNEL_DEFINES needs whitespace trimmed, otherwise the whitespace crunching
done by make fools the patsubst which is used to remove KERNEL_DEFINES from
USER_CFLAGS.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/um/Makefile

@@ -70,9 +70,12 @@ include $(srctree)/$(ARCH_DIR)/Makefile-os-$(OS)
 # in KBUILD_CFLAGS.  Otherwise, it would cause ld to complain about the two different
 # errnos.
 # These apply to kernelspace only.
+#
+# strip leading and trailing whitespace to make the USER_CFLAGS removal of these
+# defines more robust
 
-KERNEL_DEFINES = -Derrno=kernel_errno -Dsigprocmask=kernel_sigprocmask \
-	-Dmktime=kernel_mktime $(ARCH_KERNEL_DEFINES)
+KERNEL_DEFINES = $(strip -Derrno=kernel_errno -Dsigprocmask=kernel_sigprocmask \
+			 -Dmktime=kernel_mktime $(ARCH_KERNEL_DEFINES))
 KBUILD_CFLAGS += $(KERNEL_DEFINES)
 KBUILD_CFLAGS += $(call cc-option,-fno-unit-at-a-time,)