allow gles+gles2 linking at the same time (v2)

ok here is another take:
- split the huge renaming out for easier review
- it now appends hooks[] array with GLESv1 or v2, depending what's needed
- if dlopen/dlsym is used, it guarantees the the right lib is linked, even if game loads both GLESv1 and DLESv2
- otherwise if both v1 and v2 are compile-time linked, the situation remains unresolved, but maybe we can do something about it later.