build: Remove STAGING_DIR_HOST references for InstallDev/UninstallDev

build: Remove STAGING_DIR_HOST references for InstallDev/UninstallDev

Build/InstallDev no longer places a file list in
$(STAGING_DIR_HOST)/packages; this change removes the creation of
$(STAGING_DIR_HOST)/packages and the attempted removal of a
STAGING_DIR_HOST file list during package clean.

This also changes the host directory passed to Build/UninstallDev from
$(STAGING_DIR_HOST) to $(STAGING_DIR)/host, to match the directory
passed to Build/InstallDev.

Signed-off-by: Jeffery To <jeffery.to@gmail.com>