Log Message:
binutils: add upstream fixes for CVE-2021-45078.

From upstream commit log:

PR28694, Out-of-bounds write in stab_xcoff_builtin_type

PR 28694
* stabs.c (stab_xcoff_builtin_type): Make typenum unsigned.
Negate typenum earlier, simplifying bounds checking.  Correct
off-by-one indexing.  Adjust switch cases.