powerpc/xmon: Remove unused #defines

Neither REGS_PER_LINE or LAST_VOLATILE are used, nor have they ever
been as far back as I can see.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/xmon/xmon.c

@@ -166,12 +166,8 @@ extern void xmon_leave(void);
 
 #ifdef CONFIG_PPC64
 #define REG		"%.16lx"
-#define REGS_PER_LINE	4
-#define LAST_VOLATILE	13
 #else
 #define REG		"%.8lx"
-#define REGS_PER_LINE	8
-#define LAST_VOLATILE	12
 #endif
 
 #define GETWORD(v)	(((v)[0] << 24) + ((v)[1] << 16) + ((v)[2] << 8) + (v)[3])