zone: remove static_cast in float-to-int conversion

It is recommended to use library functions for conversions between
floating point and integers.  Replace static_cast (which performs
truncation) with lround (which rounds).

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Ied6633869b685d63abdbdaa249332e69b18b439b
1 file changed