MDEV-29490 Renaming internally used client API to avoid name conflicts

with C/C.
The patch introduces mariadb_capi_rename.h which is included into
mysql.h. The hew header contains macro definitions for the names being
renamed. In versions 10.6+(i.e. where sql service exists) the renaming
condition in the mariadb_capi_rename.h should be added with
&& !defined(MYSQL_DYNAMIC_PLUGIN)
and look like
The patch also contains removal of mysql.h from the api check.

Disabling false_duper-6543 test for embedded.

ha_federated.so uses C API. C API functions are being renamed in the server,
but not renamed in embedded, since embedded server library should have proper
C API, as expected by programs using it.
Thus the same ha_federated.so cannot work both for server and embedded
server library.

As all federated tests are already disabled for embedded,
federated isn't supposed to work for embedded anyway, and thus the test
is being disabled.

mysql-test/suite/plugins/t/false_dupes-6543.test

@@ -1,3 +1,4 @@
+source include/not_embedded.inc;
 #
 #    MDEV-6543 Crash if enable 'federatedx' when 'federated' plugin already enabled, and vice-versa
 #