* doc/invoke.texi: Revamp documentation of MIPS options. Remove

	-mabi=meabi, -mabi-fake-default, -mmips-as, -mgas, -mmips-tfile,
	-m4650, -mfix7000 and -(m)no-crt0.  Put endianness options first,
	then architecture options, then ABI options.  General rewording.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@75396 138bc75d-0d04-0410-961f-82ee72b054a4