arch/x86,cpu/x86: Move cpu_info initialization instructions into macro

This will help reduce duplication and make it easier to add new members
to the cpu_info struct.

BUG=b:194391185, b:179699789
TEST=Compare assembly of romstage and ramstage before and after

Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Change-Id: I31f264f4bb8b605fa3cb3bfff0d9bf79224072aa
Reviewed-on: https://review.coreboot.org/c/coreboot/+/57859
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Karthik Ramasubramanian <kramasub@google.com>

src/cpu/x86/cpu_info.S.inc

@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+/* Push struct cpu_info */
+.macro push_cpu_info index=$0
+#if CONFIG(COOP_MULTITASKING)
+	push	$0	/* *thread */
+#endif
+	push	\index	/* index */
+	push	$0	/* *cpu */
+.endm