i386: remove unused auxiliary functions in i386/subroutine.c
i386: remove unused auxiliary functions in i386/subroutine.c

Their role has been taken over by generic functionality in subroutines.

Signed-off-by: Nico Reißmann <d8255cca0642bdc1e6f9b45da9cb618d308e389b@gmail.com>

phate/jive,phate/jive,phate/jive