blkpack: Remove usage of nonstandard d_type

The man page says it's not always available and it caused problems
under some FSes. The condition is not needed in the context of
blk/, let's scrap it.

tools/blkpack.c

@@ -29,9 +29,6 @@ int main(int argc, char *argv[])
         if ((strcmp(ep->d_name, ".") == 0) || strcmp(ep->d_name, "..") == 0) {
             continue;
         }
-        if (ep->d_type != DT_REG) {
-            continue;
-        }
         int blkid = atoi(ep->d_name);
         if (blkid >= blkcnt) {
             int newcnt = blkid+1;