Remove pairing_auth, pairing_connection from recovery.

Also remove statically linking libc++, because these libraries are not
exported native shared libraries.

We are slightly over the 12MB limit for ramdisk recovery size, so let's
remove the adb pairing libraries, since they won't be used in recovery
mode.

These are only used in normal boot mode, and currently, only by adb
client. The pairing server is used by system server.

Bug: 150317254

Test: Check size of ramdisk-recovery.img in walleye, walleye-hwasam
build to be under 12MB. Also verify installed-files-recovery.txt no
longer contains libadb_pairing*.
Also put phone into recovery mode, check system/lib64 for no
libadb_pairing*.

Change-Id: Ida7c4fdc9dda2b09091b853feac8df8f125e4274