[NFC] Move MTE mode settings to a product variable.

The default list of memtag targets found in
  build/make/target/product/memtag-common.mk

Bug: 280343521
Test: no functional change
Merged-In: Ie2207f907e6559a3d54e329d09612a08afea2aa7
Change-Id: Ie2207f907e6559a3d54e329d09612a08afea2aa7
(cherry picked from commit f37c521c58cab7a5720ac38d15f297f0e3ed5928)