These functions return an error typically when the key size is an
incorrect number. AVERROR(EINVAL) is more specific than -1.
Reviewed-by: Ronald S. Bultje <rsbultje@gmail.com>
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>

crypto_bench SHA-512 results using an AMD Athlon X2 7750+, mingw32-w64 GCC 4.7.3 x86_64

Before:
lavu       SHA-512      size: 1048576  runs:   1024  time:   12.737 +- 0.147

After:
lavu       SHA-512      size: 1048576  runs:   1024  time:   11.670 +- 0.173
Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

This reduces dependancy chains and improves speed by about 2%
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>