target/arm: Mark up VNCR offsets (offsets 0x0..0xff)

target/arm: Mark up VNCR offsets (offsets 0x0..0xff)

Mark up the cpreginfo structs to indicate offsets for system
registers from VNCR_EL2, as defined in table D8-66 in rule R_CSRPQ in
the Arm ARM. This commit covers offsets below 0x100; all of these
registers are redirected to memory regardless of the value of
HCR_EL2.NV1.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Miguel Luis <miguel.luis@oracle.com>