msm: camera: isp: Handle array out of bound access

The index obtained from pointer req_frm can lead to indexing
stream_info beyond its boundary. Therefore, a bound check has been
included to avoid this.

CRs-fixed: 2008683
Change-Id: I8682e09ff2ab7ba490bbbd9e20db978493c5f3e4
Signed-off-by: Senthil Kumar Rajagopal <skrajago@codeaurora.org>
Signed-off-by: Terence Ho <terenceh@codeaurora.org>
Signed-off-by: Andy Sun <bins@codeaurora.org>