kexecboot-klibc: remove stale bbappend
kexecboot-klibc: remove stale bbappend

The recipe is now using BBCLASSEXTEND = "klibc"

Signed-off-by: Andrea Adami <58a22b0beb8ec13ae546a060c8b4c576f22f6153@gmail.com>

bluelightning/meta-handheld,bluelightning/meta-handheld