base: Style fixes in base/refcnt.hh

Change-Id: I8f4b2710bea1fe15baa1b482ff62fbab645a3690
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/40095
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
1 file changed