Fix install location of dexpreopt'd Android.mk speed apps

https://r.android.com/3148968 moved the dexpreopt artifacts of speed
apps to system_other. This CL updates the locations in
dex_preopt_odex_install.mk so that the install locations of speed apps
written in Android.mk match the install locations created by dexpreopt go binary.

Bug: 417494356
Test: verified in b/417243458#comment11
Change-Id: Ica1c685fc272470f36f7721a271f26720355d37a