After commit 3fde386 (reset [--mixed]: use diff-based reset whether or
not pathspec was given), some code can be moved to the 'reset_type ==
MIXED' check.
Let's move the code that is specific to MIXED.
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>