regulator: lp87565: Fix missing break in switch statement

Currently the LP87565_DEVICE_TYPE_LP87561_Q1 case does not have a
break statement, causing it to fall through to a dev_err message.
Fix this by adding in the missing break statement.

Addresses-Coverity: ("Missing break in switch")
Fixes: 7ee63bd7 ("regulator: lp87565: Add 4-phase lp87561 regulator support")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>