arm: mach-msm: Remove the unused rmt_storage code

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arm: mach-msm: Remove the unused rmt_storage code The rmt_storage module is no longer used. Remove the unused module and cleanup the makefile and kconfig.

CRs-Fixed: 549951
Change-Id: Ie9ebaa2209ea9fa0df05dc892504fcb882f00f29
Signed-off-by: Nikhilesh Reddy <reddyn@codeaurora.org>

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arm: mach-msm: remove rmt_storage_client header file

This was left behind after the removal of rmt_storage code

idea is taken here - https://github.com/daeiron/android_kernel_sony_apq8064/commit/c6974915864a56e7298233bcd6e49c0c15b2d00b + https://github.com/daeiron/android_kernel_sony_apq8064/commit/42f26dd7813a18d745f19f269674ca8a5c2ecd99