x86/cc: Move arch/x86/{kernel/cc_platform.c => coco/core.c}

Move cc_platform.c to arch/x86/coco/. The directory is going to be the
home space for code related to confidential computing.

Intel TDX code will land here. AMD SEV code will also eventually be
moved there.

No functional changes.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20220222185740.26228-3-kirill.shutemov@linux.intel.com

arch/x86/Kbuild

 # SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_ARCH_HAS_CC_PLATFORM) += coco/
+
 obj-y += entry/
 
 obj-$(CONFIG_PERF_EVENTS) += events/

arch/x86/coco/Makefile

+# SPDX-License-Identifier: GPL-2.0
+CFLAGS_REMOVE_core.o	= -pg
+KASAN_SANITIZE_core.o	:= n
+CFLAGS_core.o		+= -fno-stack-protector
+
+obj-y += core.o

arch/x86/kernel/Makefile

@@ -21,7 +21,6 @@ CFLAGS_REMOVE_ftrace.o = -pg
 CFLAGS_REMOVE_early_printk.o = -pg
 CFLAGS_REMOVE_head64.o = -pg
 CFLAGS_REMOVE_sev.o = -pg
-CFLAGS_REMOVE_cc_platform.o = -pg
 endif
 
 KASAN_SANITIZE_head$(BITS).o				:= n
@@ -30,7 +29,6 @@ KASAN_SANITIZE_dumpstack_$(BITS).o			:= n
 KASAN_SANITIZE_stacktrace.o				:= n
 KASAN_SANITIZE_paravirt.o				:= n
 KASAN_SANITIZE_sev.o					:= n
-KASAN_SANITIZE_cc_platform.o				:= n
 
 # With some compiler versions the generated code results in boot hangs, caused
 # by several compilation units. To be safe, disable all instrumentation.
@@ -49,7 +47,6 @@ endif
 KCOV_INSTRUMENT		:= n
 
 CFLAGS_head$(BITS).o	+= -fno-stack-protector
-CFLAGS_cc_platform.o	+= -fno-stack-protector
 
 CFLAGS_irq.o := -I $(srctree)/$(src)/../include/asm/trace
 
@@ -151,8 +148,6 @@ obj-$(CONFIG_UNWINDER_GUESS)		+= unwind_guess.o
 
 obj-$(CONFIG_AMD_MEM_ENCRYPT)		+= sev.o
 
-obj-$(CONFIG_ARCH_HAS_CC_PLATFORM)	+= cc_platform.o
-
 ###
 # 64 bit specific files
 ifeq ($(CONFIG_X86_64),y)