Fix warning about missing const qualifier
Fixes this:
In file included from libc/misc/fnmatch/fnmatch.c:235:0:
libc/misc/fnmatch/fnmatch_loop.c: In function 'internal_fnmatch':
libc/misc/fnmatch/fnmatch_loop.c:207:21: warning: initialization discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
CHAR *p_init = p;
^
libc/misc/fnmatch/fnmatch_loop.c:208:21: warning: initialization discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
CHAR *n_init = n;
Signed-off-by: Yann Sionneau <ysionneau@kalray.eu>