Reorder PPC_OPCODE_* and set PPC_OPCODE_TMR for e6500

Reorder PPC_OPCODE_* and set PPC_OPCODE_TMR for e6500

PPC_OPCODE_* renumbered to fill the gaps left by previous patches,
and reordered chronologically just because.  I kept PPC_OPCODE_TMR
because presumably it might be used in future APUinfo for e6500.

include/
	* opcode/ppc.h (PPC_OPCODE_*): Renumber and order chronologically.
	(PPC_OPCODE_SPE): Comment on this and other bits used for APUinfo.
opcodes/
	* ppc-dis.c (ppc_opts): Formatting.  Set PPC_OPCODE_TMR for e6500.
	* ppc-opc.c (powerpc_opcodes <mftmr, mttmr>): Remove now
	unnecessary E6500.