Globally disable -Wreorder-init-list.

This warning is triggered even when initializers don't have any
side effects, so it very rarely surfaces actual bugs/mistakes.
99% of the time it complains about a purely cosmetic issue.
Disable it by default in commonGlobalCFlags, which still allows
individual modules to opt into it.

Bug: 145210666
Test: presubmit
Change-Id: I671b5c457ee3d92b9cc37f020ba54e01e1a04f59