bnxt_en: set backing store type from query type

In the Linux kernel, the following vulnerability has been resolved: bnxt_en: set backing store type from query type bnxt_hwrm_func_backing_store_qcaps_v2() stores resp->type from the firmware response in ctxm->type and later uses that value to index fixed backing-store metadata arrays such as ctx_arr[] and bnxt_bstore_to_trace[]. ctxm->type is fixed by the current backing-store query type and matches the array index of ctx->ctx_arr. Set ctxm->type from the current loop variable instead of depending on resp->type. Also update the loop to advance type from next_valid_type in the for statement, which keeps the control flow simpler for non-valid and unchanged entries.