Add support for Mesa's GLES1 implementation.

Mesa reports "OpenGL ES-CM 1.1", so we need to not look for a space
after "ES", and 1.1 is still a 1.0-compatible implementation.

src/dispatch_common.c

@@ -218,7 +218,7 @@ do_dlsym(void **handle, const char *lib_name, const char *name,
 PUBLIC bool
 epoxy_is_desktop_gl(void)
 {
-    const char *es_prefix = "OpenGL ES ";
+    const char *es_prefix = "OpenGL ES";
     const char *version;
 
     if (api.begin_count)

src/gen_dispatch.py

@@ -347,7 +347,7 @@ class Generator(object):
                     loader = 'epoxy_get_proc_address({0})'
             elif api == 'gles1':
                 human_name = 'OpenGL ES 1.0'
-                condition = '!epoxy_is_desktop_gl() && epoxy_gl_version() == 10'
+                condition = '!epoxy_is_desktop_gl() && epoxy_gl_version() >= 10 && epoxy_gl_version() < 20'
                 loader = 'epoxy_gles1_dlsym({0})'
             elif api == 'glx':
                 human_name = 'GLX {0}'.format(version)