st/xlib: Include the headers in the sources list.

Yet another step towards a working 'make dist'.

Cc: José Fonseca <jfonseca@vmware.com>
Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Acked-by: José Fonseca <jfonseca@vmware.com>

src/gallium/state_trackers/glx/xlib/Makefile.sources

@@ -3,4 +3,7 @@ C_SOURCES := \
 	glx_getproc.c \
 	glx_usefont.c \
 	xm_api.c \
-	xm_st.c
+	xm_api.h \
+	xm_public.h \
+	xm_st.c \
+	xm_st.h

src/gallium/state_trackers/glx/xlib/SConscript

@@ -9,7 +9,6 @@ env.Append(CPPPATH = [
     '#/src',
     '#/src/mapi',
     '#/src/mesa',
-    '#/src/mesa/main',
 ])
 
 st_xlib = env.ConvenienceLibrary(