This commit implements the cache operation for V7M.
It is based on V7 counterpart and differs as follows:
- cache operations are memory mapped
- only Thumb instruction set is supported
- we don't handle user access faults
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Tested-by: Andras Szemzo <sza@esh.hu> Tested-by: Joachim Eastwood <manabian@gmail.com> Tested-by: Alexandre TORGUE <alexandre.torgue@st.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>