radio: RTC6226: post original tune event after scan complete

If FM is tuned to invalid freq and scan performed then invalid
freq also included in scan list. Post the tune event with
original frequency after the scan complete event posted to
user space to avoid the invalid tuned freq in scan list.

CRs-Fixed: 2681008
Change-Id: I8ac3b43742a4f92272fc5b0283fabcad2e04de5b
Signed-off-by: himta ram <hram@codeaurora.org>