dispatch: Delete unused init_dispatch functions.

dispatch: Delete unused init_dispatch functions.

The new code-generated version of _mesa_create_exec_table() populates
the entire dispatch table (except for dynamic functions) by itself; it
no longer calls separate functions to initialize parts of the dispatch
table.  This patch removes those no-longer-needed functions.

Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>