x86/mce: Merge mce_amd_inj into mce-inject

Reuse mce_amd_inj's debugfs interface so that mce-inject can
benefit from it too. The old functionality is still preserved under
CONFIG_X86_MCELOG_LEGACY.

Tested-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Yazen Ghannam <yazen.ghannam@amd.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20170613162835.30750-4-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 0efb4c9..4371b6b 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1082,7 +1082,7 @@
 	def_bool y
 
 config X86_MCE_INJECT
-	depends on X86_MCE && X86_LOCAL_APIC && X86_MCELOG_LEGACY
+	depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
 	tristate "Machine check injector support"
 	---help---
 	  Provide support for injecting machine checks for testing purposes.