beeceem: Fix missing spaces around operators and unwanted spaces around semicolons in InterfaceRx.c

Checkpatch reports missing spaces around operators; this patch
introduces spaces where needed.
Spaces before semicolons are prohibited by the official coding style
guidelines, those have been fixed as well.

Signed-off-by: Matthias Oefelein <ma.oefelein@arcor.de>
Signed-off-by: Ralph Mueck <linux-kernel@rmueck.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>