SimGear: replace include by develop/headers in SimGearTargets.cmake.

dev-games/simgear/simgear-2018.2.2.recipe

@@ -5,7 +5,7 @@ applications."
 HOMEPAGE="https://home.flightgear.org/"
 COPYRIGHT="2002-2018 Curtis Olsen and others"
 LICENSE="GNU GPL v2"
-REVISION="2"
+REVISION="3"
 SOURCE_URI="https://downloads.sourceforge.net/flightgear/simgear-$portVersion.tar.bz2"
 CHECKSUM_SHA256="f61576bc36aae36f350154749df1cee396763604c06b8a71c4b50452d9151ce5"
 PATCHES="simgear-$portVersion.patchset"
@@ -89,6 +89,10 @@ INSTALL()
 	cd build
 	cmake -P cmake_install.cmake
 
+	sed -i \
+		-e "s|\(\${_IMPORT_PREFIX}/\)include;|\1$relativeIncludeDir;|" \
+		"$libDir"/cmake/SimGear/SimGearTargets.cmake
+
 	prepareInstalledDevelLibs libSimGearCored libSimGearScened
 	fixPkgconfig