Move RECOVERY_API_VERSION and RECOVERY_FSTAB_VERSION to build/core/android_soong_config_vars.mk

This change moves the `RECOVERY_API_VERSION` and
`RECOVERY_FSTAB_VERSION` variables from
`bootable/recovery/Android.mk` to
`build/core/android_soong_config_vars.mk`.

These two variables were previously only used in `build/core/Makefile`,
and other places manually maintained synchronization using hardcoded
values. This change adds corresponding `soong_config_variables` to
keep them synchronized and avoid errors.

Bug: 339143524
Test: m misc_info
Change-Id: I90ccb5d3023d1d88ac465fc01b691b2478658b00