Move aapt flags from java_common.mk to aapt_flags.mk

The aapt flags were being set in java_common.mk, which is used by
various entry points.  host_dalvik_java_library.mk and
host_java_library.mk, and java_library.mk don't support aapt, only
package_internal.mk and static_java_library.mk do.  Move the aapt
flags into aapt_flags.mk, and include it from package_internal.mk
and static_java_library.mk.

Bug: 73885582
Test: no change to build-${TARGET_PRODUCT}.ninja
Change-Id: I124393846d37b9bbc941272cce4274121ac235ef