Use mach where possible

PKGBUILD

@@ -110,14 +110,14 @@ build() {
 
   # Do PGO
   #xvfb-run -a -n 95 -s "-extension GLX -screen 0 1280x1024x24" \
-  #  make -f client.mk build MOZ_PGO=1
-  make -f client.mk build
+  #  MOZ_PGO=1 ./mach build
+  ./mach build
   ./mach buildsymbols
 }
 
 package() {
   cd mozilla-unified
-  make -f client.mk DESTDIR="$pkgdir" INSTALL_SDK= install
+  DESTDIR="$pkgdir" ./mach install
   find . -name '*crashreporter-symbols-full.zip' -exec cp -fvt "$startdir" {} +
 
   _vendorjs="$pkgdir/usr/lib/$pkgname/browser/defaults/preferences/vendor.js"