phy: relocate and rename phy ufs files

This change contains:
1. Relocating the phy ufs files to reside under the phy driver since
this is the location of any file that implements the APIs presented in
the generic phy framework
2. Renaming ufs-msm-phy*.* files to be phy-qcom-ufs*.* files.
Since UFS is not used strictly in a specific set of targets but rather
its code is applicable to MSM, APQ, IPQ etc, any mentioning of "msm" in
the file name should be changed to "qcom".
Also, prefix of "phy-" is the naming convention of platform driver files
that reside in the phy driver.
3. As a result of the relocation of files into the phy driver,
a new path is created (include/linux/scsi/ufs) and there we expose ufs
header files that are being used also from the drivers/scsi/ufs
and from drivers/phy as well.

Change-Id: Ie5cb47718911ff711d9401a389f56fa508fcddf3
Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>