Revert "scsi: core: Move scsi_host_busy() out of host lock for waking up EH handler"

This reverts commit f5944853 which is
commit 4373534a upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: Ib6ac4094ad3b8f6361d92438635e34edb1b8b4b7
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>