diag: dci: Fix possible out of bound access

This patch fixes the possible out of bound access by accessing
only dci supported peripheral feature.

Bug: 31864832
CRs-Fixed: 1074901
Change-Id: I99b7feb4b9af8480912a0a3b3e9834f0ecd92189
Signed-off-by: Manoj Prabhu B <bmanoj@codeaurora.org>