hwrng: Add QRNG driver snapshot for kona

This is a snapshot of the qrng driver as of msm-4.14
commit <be4e0b071e9> (mm: allow vmas with vm_ops to be
speculatively handled) with changes to comply with
msm-4.19 format requirement.

Change-Id: I930b0dfd70db8b2c1ffcb98965aabe45bffbd0ba
Signed-off-by: Zhen Kong <zkong@codeaurora.org>