gmp: make this cross-buildable again after 5.1.1 update.

srcpkgs/gmp/template

@@ -2,15 +2,11 @@
 pkgname=gmp
 version=5.1.1
 revision=1
-makedepends="automake"
-crossmakedepends="zlib-devel"
 subpackages="gmp-devel"
 build_style=gnu-configure
 # Build with -fexceptions as suggested by ppl.
 CPPFLAGS="-fexceptions"
-if [ "$XBPS_MACHINE" = "x86_64" ]; then
-	configure_args="ABI=64"
-else
+if [ "$XBPS_MACHINE" = "i686" ]; then
 	cnfigure_args="ABI=32"
 fi
 configure_args="${configure_args} --enable-cxx --build=${XBPS_MACHINE}-unknown-linux-gnu"
@@ -21,7 +17,10 @@ homepage="http://gmplib.org/"
 distfiles="ftp://ftp.gmplib.org/pub/gmp-${version}/gmp-${version}.tar.xz"
 checksum=4bd64d782fdeb61aeed45b434fca5246d66baa9de76f87cba30c38460d8834c2
 
-pre_configure() {
-	sed -e "s|AM_CONFIG_HEADER|AC_CONFIG_HEADERS|g" -i configure.in
-	autoreconf -fi
-}
+if [ -n "$XBPS_CROSS_TRIPLET" ]; then
+	makedepends="automake"
+	crossmakedepends="zlib-devel"
+	pre_configure() {
+		autoreconf -fi
+	}
+fi