improve integration of pkgconfig generation

Bug: linux-sunxi#8
Signed-off-by: Yann Dirson <ydirson@o-computers.com>

Author: Yann Dirson

Makefile

@@ -1,6 +1,8 @@
 .PHONY : test
 
-all: config.mk
+pkgconfigs = egl.pc gles_cm.pc glesv2.pc
+
+all: config.mk $(pkgconfigs)
 	$(MAKE) -C include
 	$(MAKE) -C lib
 
@@ -16,12 +18,16 @@ clean:
 	$(MAKE) -C test clean
 	$(MAKE) -C lib clean
 	$(MAKE) -C include clean
-	rm -f config.mk
+	rm -f config.mk $(pkgconfigs)
 
-install: config.mk
+install: all config.mk
 	$(MAKE) -C lib install
 	$(MAKE) -C include install
-	$(MAKE) -f Makefile.pc
+	$(INSTALL_DATA) $(pkgconfigs) $(libdir)/pkgconfig
 
 test: config.mk
 	$(MAKE) -C test test
+
+%.pc: %.pc.in
+	echo "prefix=$(prefix)" > $@
+	sed -i "s/MVERSION/${MALI_VERSION}/g" $^ >> $@