hwrng: OMAP3 ROM Random Number Generator support

This driver provides kernel-side support for the Random Number
Generator hardware found on OMAP34xx processors.

This driver comes from Maemo 2.6.28 kernel and was tested on Nokia RX-51.
It is platform device because it needs board specific function for smc calls.

Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>