Disable AMD memory encryption (#438)

Under some circumpstances, having memory encryption turned on lead to silent kernel
crashes.
This is currently preventing SONiC using linux 6.1+ from being kexec'ed from Aboot
uing kexec-tools in 64 bit.
Some bisecting pointed out a change made to the way amd memory encryption is
enabled.
[c01fce9cef8491974f7f007f90281f1608400768] x86/compressed: Add SEV-SNP feature
detection/setup

Co-authored-by: mihirpat1 <[email protected]>
Co-authored-by: Saikrishna Arcot <[email protected]>

Author: 3 people

patch/kconfig-exclusions

@@ -12,6 +12,7 @@ CONFIG_MTD_SPI_NOR_USE_4K_SECTORS
 ###-> mellanox_common-end
 
 [amd64]
+CONFIG_AMD_MEM_ENCRYPT
 # Unset X86_PAT according to Broadcom's requirement
 CONFIG_X86_PAT
 CONFIG_MLXSW_PCI