egl_dri2: Silence warnings about missing initializers

egl_dri2: Silence warnings about missing initializers

egl_dri2.c: At top level:
egl_dri2.c:325:4: warning: missing initializer [-Wmissing-field-initializers]
egl_dri2.c:325:4: warning: (near initialization for 'swrast_driver_extensions[2].version') [-Wmissing-field-initializers]
egl_dri2.c:330:4: warning: missing initializer [-Wmissing-field-initializers]
egl_dri2.c:330:4: warning: (near initialization for 'swrast_core_extensions[1].version') [-Wmissing-field-initializers]

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>