Make scripts and Makefiles POSIX compliant

The bash builtin versions of the "test" (resp. "[") command allow
using "==" for string comparisons, but POSIX compatible implemen-
tations (like /usr/bin/test) insist on using "=" only. On such systems
you will see:

	$ /usr/bin/test a == a && echo OK
	/usr/bin/test: ==: binary operator expected

This patch fixes Makefiles and scripts to use POSIX style.

Signed-off-by: Wolfgang Denk <wd@denx.de>
diff --git a/board/integratorcp/split_by_variant.sh b/board/integratorcp/split_by_variant.sh
index 37ae517..79a6a9d 100755
--- a/board/integratorcp/split_by_variant.sh
+++ b/board/integratorcp/split_by_variant.sh
@@ -12,7 +12,7 @@
 cpu="arm_intcm"
 variant="unknown core module"
 
-if [ "$1" == "" ]
+if [ "$1" = "" ]
 then
 	echo "$0:: No parameters - using arm_intcm"
 else
@@ -79,7 +79,7 @@
 
 fi
 
-if [ "$cpu" == "arm_intcm" ]
+if [ "$cpu" = "arm_intcm" ]
 then
 	echo "/* Core module undefined/not ported */"	>> tmp.fil
 	echo "#define CONFIG_ARM_INTCM 1"  		>> tmp.fil