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_m68k/bootm.c b/lib_m68k/bootm.c
index 1c3b9c9..6504cc9 100644
--- a/lib_m68k/bootm.c
+++ b/lib_m68k/bootm.c
@@ -42,11 +42,8 @@
 
 static ulong get_sp (void);
 static void set_clocks_in_mhz (bd_t *kbd);
-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)
 {
 	ulong sp;
 
@@ -116,11 +113,8 @@
 	 */
 	(*kernel) (kbd, initrd_start, initrd_end, cmd_start, cmd_end);
 	/* does not return */
-	return ;
-
 error:
-	do_reset (cmdtp, flag, argc, argv);
-	return ;
+	return 1;
 }
 
 static ulong get_sp (void)