Rename __GLOBL and __GLOBL1 to __HA_GLOBL and __HA_GLOBL1, as the former are
already defined on FreeBSD.
This should be backported to 2.4, 2.3 and 2.2.
Due to length restrictions on OSX the initcall sections are called "i_"
there while they're called "init_" on other OSes. However the start and
end of sections are still called "__start_init_" and "__stop_init_",
which forces to have distinct code between the OSes. Let's switch everyone
to "i_" and rename the symbols accordingly.