crypto: msm: check potential integer overflow on AEAD req length

According to the specification of AEAD, AEAD request cryptlen is
not a Fixed maximum and assoclen is also same. This could lead to
potential integer overflow, thus allocating less memory. So we
need to check potential integer overflow on AEAD request length.

Change-Id: I58a0c5e1a6e890bad30f7865e96b7db46337158c
Signed-off-by: Zhen Kong <zkong@codeaurora.org>