ssl: remove reference to FIPS_set_mode

This was cargo-culted from the OpenSSL wiki for uninitializing OpenSSL.
This API has been removed v3.x and newer of OpenSSL, additionally
rabbitmq-c doesn't use FIPS mode, so this is likely a no-op even using
older OpenSSL.

Fixes alanxz#654
Fixes alanxz#627

Signed-off-by: GitHub <noreply@github.com>

librabbitmq/amqp_openssl.c

@@ -753,10 +753,6 @@ int amqp_uninitialize_ssl_library(void) {
   ERR_remove_state(0);
 #endif
 
-#ifndef LIBRESSL_VERSION_NUMBER
-  FIPS_mode_set(0);
-#endif
-
   CRYPTO_set_locking_callback(NULL);
   CRYPTO_set_id_callback(NULL);
   {