FROMLIST: crypto, x86/sha: Eliminate casts on asm implementations

In order to avoid CFI function prototype mismatches, this removes the
casts on assembly implementations of sha1/256/512 accelerators. The
safety checks from BUILD_BUG_ON() remain.

Additionally, this renames various arguments for clarity, as suggested
by Eric Biggers.

Signed-off-by: Kees Cook <keescook@chromium.org>
(am from https://lore.kernel.org/patchwork/patch/1179963/)
Link: https://lore.kernel.org/lkml/202001141955.C4136E9C5@keescook


Bug: 145297900
Change-Id: I331d710f11775b66229acedc59861876a2d6708b
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>