Fix the following two issues in pgxc_ctl for release 1.2.

May need similar fix in the master as well.

1) Duplicate tpedef from libpq and pgxc_ctl
2) Implicit definition of createLocalFileName() function.

Author: koichi-szk

contrib/pgxc_ctl/do_shell.c

@@ -60,7 +60,7 @@ static void prepareStdout(cmdList_t *cmdList);
  */
 jmp_buf *whereToJumpDoShell = NULL;
 jmp_buf dcJmpBufDoShell;
-pqsigfunc old_HandlerDoShell = NULL;
+pgxcsigfunc old_HandlerDoShell = NULL;
 void do_shell_SigHandler(int signum);
 
 /*

contrib/pgxc_ctl/do_shell.h

@@ -13,7 +13,7 @@
 
 extern void dcSigHandler(int signum);
 typedef enum FileType { STDIN, STDOUT, STDERR, GENERAL } FileType;
-typedef void (*pqsigfunc) (int);
+typedef void (*pgxcsigfunc) (int signo);
 extern char *createLocalFileName(FileType type, char *buf, int len);
 extern char *createRemoteFileName(FileType type, char *buf, int len);
 extern int doImmediate(char *host, char *stdIn, const char *cmd_fmt, ...) __attribute__((format(printf, 3, 4)));