build-helper/qmake: respect {C,CXX,LD}FLAGS

As of it's now, package built with build-helper/qmake natively won't
pick our CFLAGS CXXFLAGS and LDFLAGS. The result could be seen in no
debug symbol in djview.

Furthermore, cross build won't pick our hardening flags.

Let's force qmake pick our flags by using the same method as
build-style/qmake.

common/build-helper/qmake.sh

@@ -65,14 +65,36 @@ _EOF
 	# create the qmake-wrapper here because it only
 	# makes sense together with the qmake build-helper
 	# and not to interfere with e.g. the qmake build-style
+	#
+	# XXX: Intentionally quote {C,CXX,LD}FLAGS here but not in native.
+	# - Cross Build:
+	#   + base flags will be picked up from QMAKE_{C,CXX,LD}FLAGS
+	#   + hardening flags will be picked up from environment variables
+	# - Native Build:
+	#   + hardening flags will be picked up first (Makefile, qt.conf?)
+	#   + base flags will be picked up from QMAKE_{C,CXX,LD}FLAGS
+	# Maybe there're better workaround, I don't know.
         cat > "${XBPS_WRAPPERDIR}/qmake" <<_EOF
 #!/bin/sh
-exec /usr/lib/qt5/bin/qmake "\$@" -qtconf "${XBPS_WRAPPERDIR}/qt.conf"
+exec /usr/lib/qt5/bin/qmake "\$@" -qtconf "${XBPS_WRAPPERDIR}/qt.conf" \\
+	QMAKE_CFLAGS+="\${CFLAGS}" \\
+	QMAKE_CXXFLAGS+="\${CXXFLAGS}" \\
+	QMAKE_LFLAGS+="\${LDFLAGS}"
 _EOF
 else
         cat > "${XBPS_WRAPPERDIR}/qmake" <<_EOF
 #!/bin/sh
-exec /usr/lib/qt5/bin/qmake "\$@" CONFIG+=no_qt_rpath
+exec /usr/lib/qt5/bin/qmake \
+	"\$@" \
+	PREFIX=/usr \
+	QT_INSTALL_PREFIX=/usr \
+	LIB=/usr/lib \
+	QMAKE_CC=$CC QMAKE_CXX=$CXX \
+	QMAKE_LINK=$CXX QMAKE_LINK_C=$CC \
+	QMAKE_CFLAGS+="${CFLAGS}" \
+	QMAKE_CXXFLAGS+="${CXXFLAGS}" \
+	QMAKE_LFLAGS+="${LDFLAGS}" \
+	CONFIG+=no_qt_rpath
 _EOF
 fi
 chmod 755 ${XBPS_WRAPPERDIR}/qmake