kbuild: Fix gcc -x syntax

The correct syntax for gcc -x is "gcc -x assembler", not
"gcc -xassembler". Even though the latter happens to work, the former
is what is documented in the manual page and thus what gcc wrappers
such as icecream do expect.

This isn't a cosmetic change. The missing space prevents icecream from
recognizing compilation tasks it can't handle, leading to silent kernel
miscompilations.

Besides me, credits go to Michael Matz and Dirk Mueller for
investigating the miscompilation issue and tracking it down to this
incorrect -x parameter syntax.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Cc: Bernhard Walle <bernhard@bwalle.de>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>

tools/power/cpupower/Makefile

@@ -111,7 +111,7 @@ GMO_FILES = ${shell for HLANG in ${LANGUAGES}; do echo $(OUTPUT)po/$$HLANG.gmo;
 export CROSS CC AR STRIP RANLIB CFLAGS LDFLAGS LIB_OBJS
 
 # check if compiler option is supported
-cc-supports = ${shell if $(CC) ${1} -S -o /dev/null -xc /dev/null > /dev/null 2>&1; then echo "$(1)"; fi;}
+cc-supports = ${shell if $(CC) ${1} -S -o /dev/null -x c /dev/null > /dev/null 2>&1; then echo "$(1)"; fi;}
 
 # use '-Os' optimization if available, else use -O2
 OPTIMIZATION := $(call cc-supports,-Os,-O2)