qcacld-3.0: unlock chan_lock before return in wma_dfs_indicate_radar
unlock chan_lock before return in wma_dfs_indicate_radar function
in failure case.
Change-Id: I389d6479d2cd048b636230b38f135471acd38d00
CRs-Fixed: 1082162
(cherry picked from commit 41e358802ddc6722e4f1bf37b8c68ceab5e5fee5)