Require libdrm_radeon 2.4.42 for radeonsi.

It has new PCI IDs and an important tiled surface layout fix.

configure.ac

@@ -30,7 +30,7 @@ AC_SUBST([OSMESA_VERSION])
 
 dnl Versions for external dependencies
 LIBDRM_REQUIRED=2.4.24
-LIBDRM_RADEON_REQUIRED=2.4.40
+LIBDRM_RADEON_REQUIRED=2.4.42
 LIBDRM_INTEL_REQUIRED=2.4.38
 LIBDRM_NVVIEUX_REQUIRED=2.4.33
 LIBDRM_NOUVEAU_REQUIRED="2.4.33 libdrm >= 2.4.41"

scons/gallium.py

@@ -530,7 +530,7 @@ def generate(env):
     env.PkgCheckModules('XF86VIDMODE', ['xxf86vm'])
     env.PkgCheckModules('DRM', ['libdrm >= 2.4.24'])
     env.PkgCheckModules('DRM_INTEL', ['libdrm_intel >= 2.4.30'])
-    env.PkgCheckModules('DRM_RADEON', ['libdrm_radeon >= 2.4.40'])
+    env.PkgCheckModules('DRM_RADEON', ['libdrm_radeon >= 2.4.42'])
     env.PkgCheckModules('XORG', ['xorg-server >= 1.6.0'])
     env.PkgCheckModules('KMS', ['libkms >= 2.4.24'])
     env.PkgCheckModules('UDEV', ['libudev > 150'])