piglit: add patch for lack of gbm_bo_map

[Piglit Bug #100978] -- https://bugs.freedesktop.org/show_bug.cgi?id=100978

When linking against Mali 450 r6, errors like the following
can be seen:
  ../../../../lib/libpiglitutil_gl.so.0: undefined reference to `gbm_bo_unmap'
  ../../../../lib/libpiglitutil_gl.so.0: undefined reference to `gbm_bo_map'
  collect2: error: ld returned 1 exit status
  make[2]: *** [bin/point-sprite] Error 1

This is due to gbm_bo_map() and gbm_bo_unmap() being recently
added but not yet implemented by all graphics drivers.

Instead of relying on GBM's version, actually try to link
against those symbols.

Upstream-Status: Submitted [piglit@lists.freedesktop.org]

(From OE-Core rev: 2e0c8a510ee60d4ca97e58184c48995cd88a823f)

Signed-off-by: Daniel Díaz <daniel.diaz@linaro.org>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-graphics/piglit/piglit/0001-CMake-define-GBM_BO_MAP-only-when-symbol-is-found.patch

@@ -0,0 +1,48 @@
+From 6b6acee8841d092e5066b1bec2ba1c49cce4f91f Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Daniel=20D=C3=ADaz?= <daniel.diaz@linaro.org>
+Date: Thu, 4 May 2017 00:57:39 -0500
+Subject: [PATCH 1/4] CMake: define GBM_BO_MAP only when symbol is found
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+gbm_bo_map() and _unmap() have been added recently to Mesa,
+and this update may not have reached all implementations of
+GBM, such as the one provided by Mali r6, where said
+definitions can be found in the header file but not in the
+library itself. This leads to errors like the following when
+linking:
+  ../../../../lib/libpiglitutil_gl.so.0: undefined reference to `gbm_bo_unmap'
+  ../../../../lib/libpiglitutil_gl.so.0: undefined reference to `gbm_bo_map'
+  collect2: error: ld returned 1 exit status
+  make[2]: *** [bin/point-sprite] Error 1
+
+Instead of relying on the header file, actually try to link
+using that symbol to determine if PIGLIT_HAS_GBM_BO_MAP
+should be defined.
+
+Signed-off-by: Daniel Díaz <daniel.diaz@linaro.org>
+Reviewed-by: Jan Vesely <jan.vesely@rutgers.edu>
+---
+ CMakeLists.txt | 5 +++--
+ 1 file changed, 3 insertions(+), 2 deletions(-)
+
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index a4ff99e..cc26fa8 100644
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -141,8 +141,9 @@ IF(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
+ 	if(GBM_FOUND)
+ 		set(PIGLIT_HAS_GBM True)
+ 		add_definitions(-DPIGLIT_HAS_GBM)
+-		if (GBM_VERSION VERSION_EQUAL "12.1" OR GBM_VERSION VERSION_GREATER "12.1")
+-			set(PIGLIT_HAS_GBM_BO_MAP True)
++		set(CMAKE_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES} ${GBM_LIBRARIES})
++		CHECK_FUNCTION_EXISTS(gbm_bo_map PIGLIT_HAS_GBM_BO_MAP)
++		if (PIGLIT_HAS_GBM_BO_MAP)
+ 			add_definitions(-DPIGLIT_HAS_GBM_BO_MAP)
+ 		endif()
+ 	endif(GBM_FOUND)
+-- 
+1.9.1
+