powerpc/configs: Drop no longer needed CONFIG_AUDITSYSCALL

Since commit cb74ed27 ("audit: always enable syscall auditing when
supported and audit is enabled") we no longer need to set
CONFIG_AUDITSYSCALL in our defconfigs.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/configs/pseries_defconfig

@@ -3,7 +3,6 @@ CONFIG_NR_CPUS=2048
 CONFIG_SYSVIPC=y
 CONFIG_POSIX_MQUEUE=y
 CONFIG_AUDIT=y
-CONFIG_AUDITSYSCALL=y
 CONFIG_IRQ_DOMAIN_DEBUG=y
 CONFIG_NO_HZ=y
 CONFIG_HIGH_RES_TIMERS=y