hwrng: rename 'mod_init' & 'mod_exit' functions to be module-specific

hwrng: rename 'mod_init' & 'mod_exit' functions to be module-specific

Rename module_init & module_exit functions that are named
"mod_init" and "mod_exit" so that they are unique in both the
System.map file and in initcall_debug output instead of showing
up as almost anonymous "mod_init".

This is helpful for debugging and in determining how long certain
module_init calls take to execute.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Andres Salomon <dilinger@queued.net>
Cc: linux-geode@lists.infradead.org
Cc: Matt Mackall <mpm@selenic.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-crypto@vger.kernel.org
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>