[LIBS] Add SHA-256 hash support

Signed-off-by: Himanshu Chauhan <hschauhan@nulltrace.org>
[COMMANDS] Add vfs and memory commands to calculate SHA256 digest

Added vfs sha256 <filepath> and memory sha256 <region> <len>
commands to calculate the SHA-256 digest.

Signed-off-by: Himanshu Chauhan <hschauhan@nulltrace.org>
[x86] Enable SHA-256 for x86

Signed-off-by: Himanshu Chauhan <hschauhan@nulltrace.org>
[LIBS] Add support for SHA-256 password hashes

Signed-off-by: Himanshu Chauhan <hschauhan@nulltrace.org>
[x86] Make SHA256 as default password hash

Signed-off-by: Himanshu Chauhan <hschauhan@nulltrace.org>