Remove healthd from base_product.mk

healthd had been deprecated from Android P.
Does not need to support it now.

Bug: 142164625
Bug: 138284857
Test: lunch gsi_arm64-userdebug;make -j
Test: No healthd in out folder
Change-Id: I48db70f4bf39f6322bd2e80e536e2ec96b3a6408