checkstack: sort output by size and function name

checkstack: sort output by size and function name

Sort output by size and in addition by function name.  This increases
readability for cases where there are many functions with the same stack
usage.

Link: https://lkml.kernel.org/r/20231120183719.2188479-3-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Cc: Maninder Singh <maninder1.s@samsung.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>