autogen.sh: remove useless shell flag and subshells

$ ./autogen.sh
./autogen.sh: 3: ./autogen.sh: BASH_SOURCE: parameter not set

The -u flag causes this (and lots of other mysterious problems). Since
there aren't even any variables in this script, it makes no sense to
use it.

Signed-off-by: Dave Reisner <dreisner@archlinux.org>
Signed-off-by: Allan McRae <allan@archlinux.org>

autogen.sh

@@ -1,4 +1,6 @@
-#!/bin/sh -xu
+#!/bin/sh -x
 
 autoreconf -i
-(cd build-aux && (patch -Np0 -i ltmain-asneeded.patch || true))
+patch -d build-aux -Np0 -i ltmain-asneeded.patch
+
+exit 0