misc: Ensure consistent overflow error messages

Update the overflow error messages to make them consistent
across the GRUB code.

Signed-off-by: Lidong Chen <lidong.chen@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>

grub-core/fs/ntfs.c

@@ -574,7 +574,7 @@ retry:
 	      goto retry;
 	    }
 	}
-      return grub_error (GRUB_ERR_BAD_FS, "run list overflown");
+      return grub_error (GRUB_ERR_BAD_FS, "run list overflow");
     }
   ctx->curr_vcn = ctx->next_vcn;
   ctx->next_vcn += read_run_data (run, c1, 0);	/* length of current VCN */

grub-core/fs/ntfscomp.c

@@ -30,7 +30,7 @@ static grub_err_t
 decomp_nextvcn (struct grub_ntfs_comp *cc)
 {
   if (cc->comp_head >= cc->comp_tail)
-    return grub_error (GRUB_ERR_BAD_FS, "compression block overflown");
+    return grub_error (GRUB_ERR_BAD_FS, "compression block overflow");
   if (grub_disk_read
       (cc->disk,
        (cc->comp_table[cc->comp_head].next_lcn -

grub-core/video/readers/png.c

@@ -626,7 +626,7 @@ static grub_err_t
 grub_png_output_byte (struct grub_png_data *data, grub_uint8_t n)
 {
   if (--data->raw_bytes < 0)
-    return grub_error (GRUB_ERR_BAD_FILE_TYPE, "image size overflown");
+    return grub_error (GRUB_ERR_BAD_FILE_TYPE, "image size overflow");
 
   if (data->cur_column == 0)
     {