ARM: sti: Add STiH415 SOC support

The STiH415 is the next generation of HD, AVC set-top box processors for
satellite, cable, terrestrial and IP-STB markets. It is an ARM Cortex-A9
1.0 GHz, dual-core CPU.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
CC: Stephen Gallimore <stephen.gallimore@st.com>
CC: Stuart Menefy <stuart.menefy@st.com>
CC: Arnd Bergmann <arnd@arndb.de>
CC: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: Olof Johansson <olof@lixom.net>