TPM: NSC and TIS drivers X86 dependency fix

A previous commit removed its PNP dependency, that in fact wasn't
necessary, but also allowed it be built for other architectures not
supported by it. This then caused kernel oops on PPC based machines.
I'm placing a x86 dependency back correctly.
Signed-off-by: NRajiv Andrade <srajiv@linux.vnet.ibm.com>

drivers/char/tpm/Kconfig

@@ -27,6 +27,7 @@ if TCG_TPM
 
 config TCG_TIS
 	tristate "TPM Interface Specification 1.2 Interface"
+	depends on X86
 	---help---
 	  If you have a TPM security chip that is compliant with the
 	  TCG TIS 1.2 TPM specification say Yes and it will be accessible
@@ -35,6 +36,7 @@ config TCG_TIS
 
 config TCG_NSC
 	tristate "National Semiconductor TPM Interface"
+	depends on X86
 	---help---
 	  If you have a TPM security chip from National Semiconductor 
 	  say Yes and it will be accessible from within Linux.  To