powerpc/xmon: Add __printf annotation to xmon_printf()

This allows the compiler to verify the format strings vs the types of
the arguments.

Update the other prototype declarations in asm/xmon.h.

Silence warnings (triggered at W=1) by adding relevant __printf
attribute. Move #define at bottom of the file to prevent conflict with
gcc attribute.

Solves the original warning:

  arch/powerpc/xmon/nonstdio.c:178:2: error: function might be
  possible candidate for ‘gnu_printf’ format attribute

In turn this uncovered many formatting errors in xmon.c, all fixed in
this patch.
Signed-off-by: Mathieu Malaterre <malat@debian.org>
[mpe: Always use px not p, fixup the 44x specific code, tweak change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/include/asm/xmon.h

@@ -29,7 +29,7 @@ static inline void xmon_register_spus(struct list_head *list) { };
 extern int cpus_are_in_xmon(void);
 #endif
 
-extern void xmon_printf(const char *format, ...);
+extern __printf(1, 2) void xmon_printf(const char *format, ...);
 
 #endif /* __KERNEL __ */
 #endif /* __ASM_POWERPC_XMON_H */

arch/powerpc/xmon/nonstdio.h

 /* SPDX-License-Identifier: GPL-2.0 */
 #define EOF	(-1)
 
-#define printf	xmon_printf
-#define putchar	xmon_putchar
-
 extern void xmon_set_pagination_lpp(unsigned long lpp);
 extern void xmon_start_pagination(void);
 extern void xmon_end_pagination(void);
 extern int xmon_putchar(int c);
 extern void xmon_puts(const char *);
 extern char *xmon_gets(char *, int);
-extern void xmon_printf(const char *, ...);
+extern __printf(1, 2) void xmon_printf(const char *fmt, ...);
+
+#define printf	xmon_printf
+#define putchar	xmon_putchar

arch/powerpc/xmon/spu-dis.c

@@ -102,7 +102,7 @@ print_insn_spu (unsigned long insn, unsigned long memaddr)
 
   if (index == 0)
     {
-      printf(".long 0x%x", insn);
+      printf(".long 0x%lx", insn);
     }
   else
     {
@@ -134,27 +134,27 @@ print_insn_spu (unsigned long insn, unsigned long memaddr)
 	  switch (arg)
 	    {
 	    case A_T:
-	      printf("$%d",
+	      printf("$%lu",
 				     DECODE_INSN_RT (insn));
 	      break;
 	    case A_A:
-	      printf("$%d",
+	      printf("$%lu",
 				     DECODE_INSN_RA (insn));
 	      break;
 	    case A_B:
-	      printf("$%d",
+	      printf("$%lu",
 				     DECODE_INSN_RB (insn));
 	      break;
 	    case A_C:
-	      printf("$%d",
+	      printf("$%lu",
 				     DECODE_INSN_RC (insn));
 	      break;
 	    case A_S:
-	      printf("$sp%d",
+	      printf("$sp%lu",
 				     DECODE_INSN_RA (insn));
 	      break;
 	    case A_H:
-	      printf("$ch%d",
+	      printf("$ch%lu",
 				     DECODE_INSN_RA (insn));
 	      break;
 	    case A_P:
@@ -162,11 +162,11 @@ print_insn_spu (unsigned long insn, unsigned long memaddr)
 	      printf("(");
 	      break;
 	    case A_U7A:
-	      printf("%d",
+	      printf("%lu",
 				     173 - DECODE_INSN_U8 (insn));
 	      break;
 	    case A_U7B:
-	      printf("%d",
+	      printf("%lu",
 				     155 - DECODE_INSN_U8 (insn));
 	      break;
 	    case A_S3: