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: NRichard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9681)

Reviewed-by: NMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5990)

Almost all *alloc failures now set an error code.
Reviewed-by: NMatthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/5842)

Reviewed-by: NRichard Levitte <levitte@openssl.org>

This was done by the following
        find . -name '*.[ch]' | /tmp/pl
where /tmp/pl is the following three-line script:
        print unless $. == 1 && m@/\* .*\.[ch] \*/@;
        close ARGV if eof; # Close file to reset $.

And then some hand-editing of other files.
Reviewed-by: NViktor Dukhovni <viktor@openssl.org>

New functions EC_POINT_point2buf and EC_KEY_key2buf which encode
a point and allocate a buffer in one call.

New function EC_KEY_oct2key() which sets public key in an EC_KEY
structure from an encoded point.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

Following ANSI C rules, remove the casts from calls to
OPENSSL_malloc and OPENSSL_realloc.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

This gets EC_GROUP_clear_free EC_GROUP_free, EC_KEY_free,
EC_POINT_clear_free, EC_POINT_free
Reviewed-by: NKurt Roeckx <kurt@openssl.org>

Reviewed-by: NTim Hudson <tjh@openssl.org>

Submitted by: Nils Larsch

Submitted by: Nils Larsch