scripts: fix wrong usage of '==' operator

[base-files] shell-scripting: fix wrong usage of '==' operator

normally the '==' is used for invoking a regex parser and is a bashism.
all of the fixes just want to compare a string. the used busybox-ash
will silently "ignore" this mistake, but make it portable/clean at least.

this patch does not change the behavior/logic of the scripts.

Signed-off-by: Bastian Bittorf <bittorf@bluebottle.com>

SVN-Revision: 42911

target/linux/brcm2708/image/gen_rpi_sdcard_img.sh

@@ -1,7 +1,7 @@
 #!/usr/bin/env bash
 
 set -x 
-[ $# == 5 ] || {
+[ $# -eq 5 ] || {
     echo "SYNTAX: $0 <file> <bootfs image> <rootfs image> <bootfs size> <rootfs size>"
     exit 1
 }