classes: Drop ';' delimiter from ROOTFS/IMAGE*COMMAND variables

Originally these were shell functions but they have long since been processed by
bb.build.exec_func(). Since we no longer need shell syntax, we can drop the ';'
delimiters and just use a space separated string.

This cleans up the variable and quietly removes any stray ';' that do happen to
still make it in.

(From OE-Core rev: c3365dfd9ddd7fbe70b62e0f11166e57a8ca6f73)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes/extrausers.bbclass

@@ -23,7 +23,7 @@ inherit useradd_base
 PACKAGE_INSTALL:append = " ${@['', 'base-passwd shadow'][bool(d.getVar('EXTRA_USERS_PARAMS'))]}"
 
 # Image level user / group settings
-ROOTFS_POSTPROCESS_COMMAND:append = " set_user_group;"
+ROOTFS_POSTPROCESS_COMMAND:append = " set_user_group"
 
 # Image level user / group settings
 set_user_group () {