sysutils/opencorsairlink: fix build on GCC architectures

Linking to libm is required to build this port with GCC:
/wrkdirs/usr/ports/sysutils/opencorsairlink/work/OpenCorsairLink-4234f4f/protocol/rmi/core.c:49: undefined reference to `pow'

PR: 241457
Approved by: linimon (mentor), lifanov (maintainer timeout)