* remote-mips.c (common_breakpoint): Prevent 64-bit addresses

	* remote-mips.c (common_breakpoint): Prevent 64-bit addresses
	from being sent to 32-bit targets by masking off upper bits.
	* mips-tdep.c (heuristic_proc_start): Mask off upper 32 bits
	of PC on 32-bit targets.
	(mips16_heuristic_proc_desc): Recognize 'addiu s1,sp,n' as a
	frame setup instruction.
	(mips32_heuristic_proc_desc): Fix warning found by gcc -Wall.
	(mips16_skip_prologue): Recognize 'addiu s1,sp,n' as a valid
	prologue instruction.  Fix warnings and bugs found by gcc -Wall.
	* buildsym.c (finish_block): Improve handling of overlapping blocks;
	fixes problem on MIPS16 printing function arguments.