crypto: Fix build on AMD64
crypto: Fix build on AMD64

- isrcry_sha1_final() was attempting to use STORE32H() to store a
64-bit quantity, when what it actually wanted was the lower 32
bits of that quantity.  This caused build failures on AMD64.  Fix this.

cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr