Prebuild: Remove --compile-pic and -Xnorelocate.

The --compile-pic argument is obsolete, all generated code
is now PIC.

The -Xnorelocate is ignored by dex2oat since
    https://android-review.googlesource.com/771001
where the option was reinterpreted from "use patchoat if
needed" to "relocate the boot image in memory if possible"
and dex2oat forbids that relocation.

Test: Pixel 2 XL boots.
Bug: 77856493
Change-Id: I60cdf81267a129be8a482af26fb865110561268e