Update PKGBUILD (#1836)

mingw-w64-libmicrohttpd/PKGBUILD

@@ -7,7 +7,7 @@ _realname=libmicrohttpd
 pkgbase=mingw-w64-${_realname}
 pkgname="${MINGW_PACKAGE_PREFIX}-${_realname}"
 pkgver=0.9.50
-pkgrel=3
+pkgrel=4
 pkgdesc="GNU libmicrohttpd is a small C library that is supposed to make it easy to run an HTTP server as part of another application (mingw-w64)"
 arch=('any')
 url="https://www.gnu.org/software/libmicrohttpd"
@@ -24,7 +24,7 @@ sha256sums=('d1b6385068abded29b6470e383287aa7705de05ae3c08ad0bf5747ac4dc6ebd7')
 build() {
   [[ -d ${srcdir}/build-${MINGW_CHOST} ]] && rm -rf ${srcdir}/build-${MINGW_CHOST}
   mkdir -p ${srcdir}/build-${MINGW_CHOST} && cd ${srcdir}/build-${MINGW_CHOST}
-  CFLAGS+=" -D_POSIX_C_SOURCE"
+  CFLAGS+=" -DWINVER=0x0600 -D_WIN32_WINNT=0x0600 -D_POSIX_C_SOURCE"
   ../${_realname}-${pkgver}/configure \
     --prefix=${MINGW_PREFIX} \
     --build=${MINGW_CHOST} \