From: Arnd Bergmann <arnd@arndb.de>

Enable basic profiling code on s390 depending on CONFIG_PROFILING, not
CONFIG_OPROFILE.

CONFIG_PROFILING should enable the generic profiling code here, even if
CONFIG_OPROFILE is not set.  Note that the identical code on i386 is always
compiled in, regardless of CONFIG_PROFILING and CONFIG_OPROFILE.