mfd: Add a core driver for TI TPS61050/TPS61052 chips v2

The TPS61050/TPS61052 are boost converters, LED drivers, LED flash
drivers and a simple GPIO pin chips.

Cc: Liam Girdwood <lrg@slimlogic.co.uk>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Jonas Aberg <jonas.aberg@stericsson.com>
Cc: Ola Lilja <ola.o.lilja@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>