radv: fix include order for installed headers v2

In situations where libdrm_amdgpu and mesa are installed to the same
location, the mesa installed headers will take precedence over the git
source headers.

This is due to the AMDGPU_CFLAGS containing the install directory.

This situation can cause build errors if the git version of a header is
newer than the currently installed version of a header (e.g. git pull
updates vulkan.h)

Note: using the same install prefix for mesa and libdrm is probably a
common occurrence since it is described in the radeonBuildHowTo wiki:
https://www.x.org/wiki/radeonBuildHowTo/

v2: added sign-off

Signed-off-by: Andres Rodriguez <andresx7@gmail.com>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
(cherry picked from commit a3ad6a34c6)
Nominated-by: Emil Velikov <emil.velikov@collabora.com>

src/amd/vulkan/Makefile.am

@@ -32,9 +32,6 @@ lib_LTLIBRARIES = libvulkan_radeon.la
 # The gallium includes are for the util/u_math.h include from main/macros.h
 
 AM_CPPFLAGS = \
-	$(AMDGPU_CFLAGS) \
-	$(VALGRIND_CFLAGS) \
-	$(DEFINES) \
 	-I$(top_srcdir)/include \
 	-I$(top_builddir)/src \
 	-I$(top_srcdir)/src \
@@ -48,7 +45,10 @@ AM_CPPFLAGS = \
 	-I$(top_srcdir)/src/mesa \
 	-I$(top_srcdir)/src/mesa/drivers/dri/common \
 	-I$(top_srcdir)/src/gallium/auxiliary \
-	-I$(top_srcdir)/src/gallium/include
+	-I$(top_srcdir)/src/gallium/include \
+	$(AMDGPU_CFLAGS) \
+	$(VALGRIND_CFLAGS) \
+	$(DEFINES)
 
 AM_CFLAGS = \
 	$(VISIBILITY_CFLAGS) \