reg: qcom: call regulatory callback for self managed hints

Currently, kernel ignores the regulatory hint if wiphy flag
REGULATORY_WIPHY_SELF_MANAGED is set. This would lead to drop of
hints sent directly to kernel from user-space. To fix, call the driver
callback with the request.

CRs-Fixed: 2183721
Change-Id: Ic6d17ce8c3e9b889f618f3494672020bb1c98c42
Signed-off-by: Amar Singhal <asinghal@codeaurora.org>