MIPS: optimize and fix ELF sections

MIPS: optimize and fix ELF sections

Discard ABI related sections which are not required for debugging.
Rearrange debug sections similar to Linux. Remove the remaining
explicitely specified sections in the unused part because those
sections are not created anymore or because the linker puts them
by default at the end of the ELF binary.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Tested-by: Ezequiel Garcia <ezequiel@collabora.com>