hwrng: ks-sa - move TI Keystone driver into the config menu structure

Move the TI Keystone hardware random number generator into the
same menu as all of the other hardware random number generators.

This makes the driver config be listed in the correct place in
the kconfig tools.

Fixes: eb428ee0 ("hwrng: ks-sa - add hw_random driver")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Vitaly Andrianov <vitalya@ti.com>
Cc: Tero Kristo <t-kristo@ti.com>
Cc: Murali Karicheri <m-karicheri2@ti.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Matt Mackall <mpm@selenic.com>
Cc: linux-crypto@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>