adb: fix 64-bit build

strlen returns a size_t, but the * modifier in printf expects an int.
On arm64 size_t != int.

Change-Id: I11e84a7b62c935162abc0aba910d14e63d11efd3
diff --git a/commandline.c b/commandline.c
index bcfdba0..b92162f 100644
--- a/commandline.c
+++ b/commandline.c
@@ -602,7 +602,7 @@
         }
     }
 
-    printf("\rTotal xfer: %.2fx%*s\n", (double)xfer / (sz ? sz : 1), strlen(fn)+10, "");
+    printf("\rTotal xfer: %.2fx%*s\n", (double)xfer / (sz ? sz : 1), (int)strlen(fn)+10, "");
 
   done:
     if (fd >= 0) adb_close(fd);