s390/kexec: do not automatically select KEXEC option

Following commit dccf78d3 ("kernel/Kconfig.kexec: drop
select of KEXEC for CRASH_DUMP") also drop automatic KEXEC
selection for s390 while set CONFIG_KEXEC=y explicitly for
defconfig and debug_defconfig targets. zfcpdump_defconfig
target gets CONFIG_KEXEC unset as result, which is right
and consistent with CONFIG_KEXEC_FILE besides.
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

arch/s390/Kconfig

@@ -216,7 +216,6 @@ config S390
 	select HAVE_VIRT_CPU_ACCOUNTING_IDLE
 	select IOMMU_HELPER		if PCI
 	select IOMMU_SUPPORT		if PCI
-	select KEXEC
 	select MMU_GATHER_MERGE_VMAS
 	select MMU_GATHER_NO_GATHER
 	select MMU_GATHER_RCU_TABLE_FREE

arch/s390/configs/debug_defconfig

@@ -40,6 +40,7 @@ CONFIG_SCHED_AUTOGROUP=y
 CONFIG_EXPERT=y
 # CONFIG_SYSFS_SYSCALL is not set
 CONFIG_PROFILING=y
+CONFIG_KEXEC=y
 CONFIG_KEXEC_FILE=y
 CONFIG_KEXEC_SIG=y
 CONFIG_CRASH_DUMP=y

arch/s390/configs/defconfig

@@ -38,6 +38,7 @@ CONFIG_SCHED_AUTOGROUP=y
 CONFIG_EXPERT=y
 # CONFIG_SYSFS_SYSCALL is not set
 CONFIG_PROFILING=y
+CONFIG_KEXEC=y
 CONFIG_KEXEC_FILE=y
 CONFIG_KEXEC_SIG=y
 CONFIG_CRASH_DUMP=y