PM: AVS: Drop the avs directory and the corresponding Kconfig

All avs drivers have now been moved to their corresponding soc specific
directories. Additionally, they don't depend on the POWER_AVS Kconfig
anymore. Therefore, let's simply drop the drivers/power/avs directory
altogether.

Cc: Nishanth Menon <nm@ti.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/power/Kconfig

 # SPDX-License-Identifier: GPL-2.0-only
-source "drivers/power/avs/Kconfig"
 source "drivers/power/reset/Kconfig"
 source "drivers/power/supply/Kconfig"

drivers/power/Makefile

 # SPDX-License-Identifier: GPL-2.0-only
-obj-$(CONFIG_POWER_AVS)		+= avs/
 obj-$(CONFIG_POWER_RESET)	+= reset/
 obj-$(CONFIG_POWER_SUPPLY)	+= supply/

drivers/power/avs/Kconfig

-# SPDX-License-Identifier: GPL-2.0-only

drivers/power/avs/Makefile

-# SPDX-License-Identifier: GPL-2.0-only