drivers: thermal: Include qcom folder for ARCH_QCOM

The qcom folder has thermal drivers that are specific to qcom devices
and it right now dependes on Qcom tsens kconfig to include the directory.

Remove the dependency and enable the qcom folder to be included if the
ARCH_QCOM config is enabled.

Change-Id: I258d451ed6af1117e1309915e9b75dcb4eed9921
Signed-off-by: Ram Chandrasekar <rkumbako@codeaurora.org>