gdb: xtensa: fix on 64-bit hosts

On 64-bit hosts unsigned long is 64 bit.  Use uint32_t instead.

gdb/
2014-01-22  Baruch Siach  <baruch@tkos.co.il>

	* xtensa-tdep.h (xtensa_elf_greg_t): Change type to uint32_t.

gdb/ChangeLog

@@ -1,3 +1,7 @@
+2014-01-22  Baruch Siach  <baruch@tkos.co.il>
+
+	* xtensa-tdep.h (xtensa_elf_greg_t): Change type to uint32_t.
+
 2014-01-22  Pedro Alves  <palves@redhat.com>
 
 	* xtensa-config.c: Include defs.h.

gdb/xtensa-tdep.h

@@ -84,7 +84,7 @@ typedef enum
 /* Xtensa ELF core file register set representation ('.reg' section).
    Copied from target-side ELF header <xtensa/elf.h>.  */
 
-typedef unsigned long xtensa_elf_greg_t;
+typedef uint32_t xtensa_elf_greg_t;
 
 typedef struct
 {