libraw: add upstream patch link

mingw-w64-libraw/PKGBUILD

@@ -31,6 +31,7 @@ sha256sums=('dc1b486c2003435733043e4e05273477326e51c3ea554c6864a4eafaff1004a6'
 prepare() {
   cd "${srcdir}"/${_realname}-${pkgver}
   patch -p1 -i "${srcdir}/LibRaw_obsolete-macros.patch"
+  # From https://github.com/LibRaw/LibRaw/commit/4c954948ba2de262b9cb23a1843fb8651aa3dcc1
   patch -p1 -i "${srcdir}/LibRaw_force-openmp.patch"
 
   autoreconf -ifv
@@ -54,5 +55,5 @@ package() {
 
   make install DESTDIR="${pkgdir}"
 
-  install -Dm644 ${srcdir}/${_realname}-${pkgver}/LICENSE.LGPL ${pkgdir}${MINGW_PREFIX}/share/licenses/libraw/LICENSE
+  install -Dm644 "${srcdir}"/${_realname}-${pkgver}/LICENSE.LGPL "${pkgdir}"${MINGW_PREFIX}/share/licenses/libraw/LICENSE
 }