Fix header file include guard names

Fix header file include guard names

Make the include guards consistent by renaming them systematically according
to the naming conventions below

The public header files (in the 'include/openssl' directory) are not changed
in 1.1.1, because it is a stable release.

For the private header files files, the guard names try to match the path
specified in the include directives, with all letters converted to upper case
and '/' and '.' replaced by '_'. An extra 'OSSL_' is added as prefix.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9681)