OpenSSL 3.0 Compatibility

[remicollet]

AS this will be the default version in Fedora 36 and RHEL 9 (and Centos and other clones)

For now:

$ make
cc -c -pipe -fPIC -fvisibility=hidden -O -W -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wmissing-prototypes -Werror -g   -I src -I build -I/opt/openssl/include  \
                      \
                     \
-o build/src/nxt_openssl.o \
-MMD -MF build/src/nxt_openssl.dep -MT build/src/nxt_openssl.o \
src/nxt_openssl.c
src/nxt_openssl.c: In function 'nxt_tls_ticket_key_callback':
src/nxt_openssl.c:820:5: error: 'HMAC_Init_ex' is deprecated: Since OpenSSL 3.0 [-Werror=deprecated-declarations]
  820 |     if (HMAC_Init_ex(hctx, ticket[i].hmac_key, ticket[i].size, digest, NULL)
      |     ^~
In file included from /opt/openssl/include/openssl/ssl.h:37,
                 from src/nxt_openssl.c:9:
/opt/openssl/include/openssl/hmac.h:43:27: note: declared here
   43 | OSSL_DEPRECATEDIN_3_0 int HMAC_Init_ex(HMAC_CTX *ctx, const void *key, int len,
      |                           ^~~~~~~~~~~~
src/nxt_openssl.c: In function 'nxt_openssl_copy_error':
src/nxt_openssl.c:1784:9: error: 'ERR_get_error_line_data' is deprecated: Since OpenSSL 3.0 [-Werror=deprecated-declarations]
 1784 |         err = ERR_get_error_line_data(NULL, NULL, &data, &flags);
      |         ^~~
In file included from src/nxt_openssl.c:11:
/opt/openssl/include/openssl/err.h:413:15: note: declared here
  413 | unsigned long ERR_get_error_line_data(const char **file, int *line,
      |               ^~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
make: *** [build/Makefile:1375: build/src/nxt_openssl.o] Error 1

[ac000]

This has been handled in commit 5665838