staging: omap-thermal: Add a MAINTAINERS entry for TI bandgap and thermal driver

Add myself as maintainer of the TI bandgap and thermal driver.

CC: Santosh Shilimkar <santosh.shilimkar@ti.com>
CC: Zhang Rui <rui.zhang@intel.com>

Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>