s390/traps: only define is_valid_bugaddr() under CONFIG_GENERIC_BUG

When building with -Wmissing-prototypes without CONFIG_GENERIC_BUG, there
is a warning about a missing prototype for is_valid_bugaddr():

  arch/s390/kernel/traps.c:46:5: warning: no previous prototype for 'is_valid_bugaddr' [-Wmissing-prototypes]
     46 | int is_valid_bugaddr(unsigned long addr)
        |     ^~~~~~~~~~~~~~~~

The prototype is only declared with CONFIG_GENERIC_BUG, so only define the
function under the same condition to clear up the warning, which matches
other architectures.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Nathan Chancellor <[email protected]>
Reviewed-by: Alexander Gordeev <[email protected]>
Cc: Christian Borntraeger <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Jan Höppner <[email protected]>
Cc: Stefan Haberland <[email protected]>
Cc: Sven Schnelle <[email protected]>
Cc: Vasily Gorbik <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions