Fix redefinition building error (blueprint)

Fix redefinition building error (blueprint)

Fixes the following building errors:

In file included from external/minigbm/amdgpu.c:16:
In file included from external/minigbm/dri.h:13:
external/mesa/include/GL/internal/dri_interface.h:46:22: error: redefinition of typedef 'drm_context_t' is a C11 feature [-Werror,-Wtypedef-redefinition]
typedef unsigned int drm_context_t;
                     ^
external/libdrm/include/drm/drm.h:77:22: note: previous definition is here
typedef unsigned int drm_context_t;
                     ^