object-file.c: split up declaration of unrelated variables

object-file.c: split up declaration of unrelated variables

Split up the declaration of the "ret" and "re_allocated"
variables. It's not our usual style to group variable declarations
simply because they share a type, we'd only prefer to do so when the
two are closely related (e.g. "int i, j"). This change makes a
subsequent and meaningful change's diff smaller.

Signed-off-by: Ævar Arnfjörð Bjarmason <redacted>
Signed-off-by: Junio C Hamano <redacted>