clean up x86 i/o checks

Rather than hardcode a specific mips toolchain, do a build-time test to
see if the target is x86 based.

BUG=chromium:443783
TEST=link still includes comm-lpc
TEST=arm64 omits comm-lpc
BRANCH=none

Change-Id: I0253df6cbe89bee231ec643dd6bb3498eb040708
Reviewed-on: https://chromium-review.googlesource.com/265793
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>

util/build.mk

@@ -10,10 +10,7 @@ host-util-bin=ectool lbplay stm32mon ec_sb_firmware_update lbcc
 build-util-bin=ec_uartd iteflash
 
 comm-objs=$(util-lock-objs:%=lock/%) comm-host.o comm-dev.o
-ifneq ($(HOSTCC),mipsel-cros-linux-gnu-gcc)
-comm-objs+=comm-lpc.o
-endif
-comm-objs+=comm-i2c.o
+comm-objs+=comm-lpc.o comm-i2c.o
 
 ectool-objs=ectool.o ectool_keyscan.o misc_util.o ec_flash.o $(comm-objs)
 ec_sb_firmware_update-objs=ec_sb_firmware_update.o $(comm-objs) misc_util.o

util/comm-lpc.c

@@ -3,6 +3,9 @@
  * found in the LICENSE file.
  */
 
+/* The I/O asm funcs exist only on x86. */
+#if defined(__i386__) || defined(__x86_64__)
+
 #include <stdint.h>
 #include <stdio.h>
 #include <sys/io.h>
@@ -309,3 +312,5 @@ int comm_init_lpc(void)
 	ec_readmem = ec_readmem_lpc;
 	return 0;
 }
+
+#endif

util/ectool.c

@@ -1186,7 +1186,8 @@ int cmd_pd_get_amode(int argc, char *argv[])
 	return -1;
 }
 
-#ifdef __x86_64
+/* The I/O asm funcs exist only on x86. */
+#if defined(__i386__) || defined(__x86_64__)
 #include <sys/io.h>
 
 int cmd_serial_test(int argc, char *argv[])