libselinux: pkg-config to figure out where ruby include files are located

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Dan Walsh <dwalsh@redhat.com>
diff --git a/libselinux/src/Makefile b/libselinux/src/Makefile
index 985842d..5ddc011 100644
--- a/libselinux/src/Makefile
+++ b/libselinux/src/Makefile
@@ -15,7 +15,7 @@
 PYLIBDIR ?= $(LIBDIR)/$(PYLIBVER)
 RUBYLIBVER ?= $(shell ruby -e 'print RUBY_VERSION.split(".")[0..1].join(".")')
 RUBYPLATFORM ?= $(shell ruby -e 'print RUBY_PLATFORM')
-RUBYINC ?= $(LIBDIR)/ruby/$(RUBYLIBVER)/$(RUBYPLATFORM)
+RUBYINC ?= $(shell pkg-config --cflags ruby-$(RUBYLIBVER))
 RUBYINSTALL ?= $(LIBDIR)/ruby/site_ruby/$(RUBYLIBVER)/$(RUBYPLATFORM)
 LIBBASE=$(shell basename $(LIBDIR))
 
@@ -96,7 +96,7 @@
 	$(CC) $(filter-out -Werror, $(CFLAGS)) $(PYINC) -fPIC -DSHARED -c -o $@ $<
 
 $(SWIGRUBYLOBJ): $(SWIGRUBYCOUT)
-	$(CC) $(filter-out -Werror, $(CFLAGS)) -I$(RUBYINC) -fPIC -DSHARED -c -o $@ $<
+	$(CC) $(filter-out -Werror, $(CFLAGS)) $(RUBYINC) -fPIC -DSHARED -c -o $@ $<
 
 $(SWIGSO): $(SWIGLOBJ)
 	$(CC) $(CFLAGS) $(LDFLAGS) -shared -o $@ $< -L. -lselinux -L$(LIBDIR) $(PYTHONLIBDIR) -Wl,-soname,$@,-z,defs