Fixed bug in underflow handling of page during delete found by running sql_bench

storage/maria/ma_delete.c:
  Remove wrong optimization (first_key is not related to keypos value at this point)
storage/maria/maria_chk.c:
  Added printing of forgotten option

storage/maria/ma_delete.c

@@ -1112,7 +1112,7 @@ static int underflow(register MARIA_HA *info, MARIA_KEYDEF *keyinfo,
     MARIA_KEY_PARAM anc_key_inserted;
     size_t tmp_length;
 
-    if (first_key)
+    if (keypos == anc_buff + share->keypage_header + key_reflength)
       anc_pos= 0;				/* First key */
     else
     {

storage/maria/maria_chk.c

@@ -443,6 +443,8 @@ static void usage(void)
 #endif
                       printf(", they will be used\n\
                       in a round-robin fashion.\n\
+  --require-control-file  Abort if we can't find/read the maria_log_control\n\
+                          file\n\
   -s, --silent	      Only print errors.  One can use two -s to make\n\
 		      maria_chk very silent.\n\
   -v, --verbose       Print more information. This can be used with\n\