make FUNC_CHECK(), TYPE_CHECK() and HEADER_CHECK() more general and
they can be set to a scope, like "eina", then all symbols are prefixed
with that. The scope is created with CHECK_INIT(), and
EFL_HEADER_CHECKS_FINALIZE() will finish that.
This makes it possible for cmake/config/eina.cmake +
cmake/post/eina.cmake to add stuff to the generated file, better than
hand edit the template.
CHECK_APPEND_DEFINE(name val) is now the base to add symbols to the
generated file in the current scope.
Then convert cmake/config/eina.cmake to use that and match the
autotools values (were a bit off).
This exposed enabling valgrind was broken due incorrect pkg-config
usage with cmake (it's not obvious), it was using just the libraries,
while LDFLAGS are needed to get -L/usr/lib/valgrind. Then also convert
to CFLAGS provided by pkg-config and make that automatic for
PKG_CONFIG_REQUIRES and PKG_CONFIG_REQUIRES_PRIVATE.
Also, eina-mempool modules use valgrind and must use that now that's