Apart from public and internal header files, there is a third type called
local header files, which are located next to source files in the source
directory. Currently, they have different suffixes like
'*_lcl.h', '*_local.h', or '*_int.h'
This commit changes the different suffixes to '*_local.h' uniformly.
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9681)
