libkmod: rename kmod_elf_get_strings()

libkmod: rename kmod_elf_get_strings()

Rename kmod_elf_get_strings() to kmod_elf_get_modinfo_strings() and fold
the section name within, instead of passing it as an argument.

This aligns better with the other kmod_elf function names and will allow
us to tweak the kmod_elf_get_section() handling with later commit.

Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: Tobias Stoeckmann <tobias@stoeckmann.org>
Link: https://github.com/kmod-project/kmod/pull/210
Signed-off-by: Lucas De Marchi <lucas.de.marchi@gmail.com>