bootm: refactor do_reset and os boot function args

There is no need for each OS specific function to call do_reset() we
can just do it once in bootm. This means its feasible on an error for
the OS boot function to return.

Also, remove passing in cmd_tbl_t as its not needed by the OS boot
functions.  flag isn't currently used but might be in the future so
we left it alone.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/lib_mips/bootm.c b/lib_mips/bootm.c
index 9869c33..c1bf21e 100644
--- a/lib_mips/bootm.c
+++ b/lib_mips/bootm.c
@@ -43,15 +43,11 @@
 static void linux_params_init (ulong start, char * commandline);
 static void linux_env_set (char * env_name, char * env_val);
 
-extern int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]);
-
-void do_bootm_linux (cmd_tbl_t * cmdtp, int flag, int argc, char *argv[],
-		     bootm_headers_t *images)
+int do_bootm_linux(int flag, int argc, char *argv[], bootm_headers_t *images)
 {
 	void	(*theKernel) (int, char **, char **, int *);
 	char	*commandline = getenv ("bootargs");
 	char	env_buf[12];
-	int	ret;
 	char	*cp;
 
 	/* find kernel entry point */
@@ -103,11 +99,7 @@
 
 	theKernel (linux_argc, linux_argv, linux_env, 0);
 	/* does not return */
-	return;
-
-error:
-	do_reset (cmdtp, flag, argc, argv);
-	return;
+	return 1;
 }
 
 static void linux_params_init (ulong start, char *line)