target/arm: Make set_feature() available for other files

target/arm: Make set_feature() available for other files

Move the common set_feature() and unset_feature() functions
from cpu.c and cpu64.c to cpu.h.

Suggested-by: Peter Maydell <[email protected]>
Signed-off-by: Thomas Huth <[email protected]>
Reviewed-by: Richard Henderson <[email protected]>
Reviewed-by: Eric Auger <[email protected]>
Signed-off-by: Philippe Mathieu-Daudé <[email protected]>
Message-id: 20200504172448[email protected]
Message-ID: <20190921150420[email protected]>
[PMD: Split Thomas's patch in two: set_feature, cpu_register]
Signed-off-by: Philippe Mathieu-Daudé <[email protected]>
Signed-off-by: Peter Maydell <[email protected]>