fix the mangled function strcmp

Fix the mangled function strcmp so that it compares all of the string
except for the numbered parts.  foo.isra.35 should match foo.isra.1, but
not foo.isra.35.part.36.

Fixes #352.
imo, this whole while block should be in a separate function with s and b as arguments i.e. sonmething like kpatch_sym_strcmp(sym->name, basesym->name) that returns the value of found.