Revert "Add support for only starting 64 bit zygote."

This reverts commit da94c7f6.

Reason for revert: It appears this change slows down boot on normal devices.

Technically, this change is not necessary, but it prevents starting the secondary and having it throw an error in the only run 64 bit zygote config. But it's easier to throw the error than slow down boot up.

Bug: 238971179

Test: Verified that on a 64 with 32 config, the secondary zygote
Test: starts but exits.
Change-Id: I7ab0496a402db83e70168d52e5d5911b82a3b06a