Replace duplicated KENB_STAR_TO_BIT_STRING and
KGNB_STAR_TO_BIT_STRING macros with the unified
AS_KEY_STAR_TO_BIT_STRING helper across X2AP,
XNAP, M2AP, and M3AP code paths.
Also switch allocation to calloc_or_fail for
safer memory handling.
No functional change intended.
Signed-off-by: Rakesh BB <rakesh.bb@fsid-iisc.in>
e33ffd5e8c