Set an explicit path for the initrd scripts

If we don't set PATH, then the shell will specify one for us.
Busybox adds the sbin dirs, but bash does not. I hit an
issue where bash (among other things) ended up in my initrd
and the boot scripts failed due to a bad default PATH. While
that is a separate issue, we should not be at the mercy of the
shell's default PATH. Update the initrdscripts to all specify:

PATH=/sbin:/bin:/usr/sbin:/usr/bin

(From OE-Core rev: 4617ae0f433876037c2c9a0dfdb5e373e7a5c77b)

Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-core/initrdscripts/files/init-boot.sh

@@ -1,5 +1,7 @@
 #!/bin/sh
 
+PATH=/sbin:/bin:/usr/sbin:/usr/bin
+
 mkdir /proc
 mkdir /sys
 mount -t proc proc /proc

meta/recipes-core/initrdscripts/files/init-install.sh

@@ -5,6 +5,8 @@
 # install.sh [device_name] [rootfs_name] [video_mode] [vga_mode]
 #
 
+PATH=/sbin:/bin:/usr/sbin:/usr/bin
+
 # We need 20 Mb for the boot partition
 boot_size=20
 

meta/recipes-core/initrdscripts/files/init-live.sh

@@ -1,5 +1,7 @@
 #!/bin/sh
 
+PATH=/sbin:/bin:/usr/sbin:/usr/bin
+
 ROOT_MOUNT="/rootfs/"
 ROOT_IMAGE="rootfs.img"
 MOUNT="/bin/mount"
@@ -12,7 +14,7 @@ early_setup() {
     mount -t proc proc /proc
     mount -t sysfs sysfs /sys
     udevd --daemon
-    /sbin/udevadm trigger --action=add
+    udevadm trigger --action=add
 }
 
 read_args() {