Revert "drivers: msm: create the folder for msm platform drivers"

This reverts commit b54a0482.
Compilation error is observed in drivers/platform folder,
because no driver is added into drivers/platform/msm folder yet.

Here is the compilation error -
make[3]: *** [drivers/platform/built-in.o] Error 1
make[2]: *** [drivers/platform] Error 2

Change-Id: I80a8dc0b647576b5a370e4cc38b2d10814c9470f
Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>