Issue 49306 - make -f rpm.mk rpms produces build without tcmalloc enabled

Bug Description:
Configure option changed from --with-tcmalloc to --enable-tcmalloc,
but provided spec file template was not updated.

Fix Description:
Update spec file template

https://pagure.io/389-ds-base/issue/49306

Reviewed by: ???

rpm/389-ds-base.spec.in

@@ -263,7 +263,7 @@ ASAN_FLAGS="--enable-asan --enable-debug"
 %endif
 
 %if %{use_tcmalloc}
-TCMALLOC_FLAGS="--with-tcmalloc"
+TCMALLOC_FLAGS="--enable-tcmalloc"
 %endif
 
 # Rebuild the autotool artifacts now.