Add support for the 'x86' unified kernel arch in conftest.sh

--- NVIDIA-Linux-x86-256.25/kernel/conftest.sh
+++ NVIDIA-Linux-x86-256.25/kernel/conftest.sh
@@ -101,7 +101,7 @@ build_cflags() {
 
     if [ "$OUTPUT" != "$SOURCES" ]; then
         MACH_CFLAGS="-I$HEADERS/asm-$ARCH/mach-default"
-        if [ "$ARCH" = "i386" -o "$ARCH" = "x86_64" ]; then
+        if [ "$ARCH" = "i386" -o "$ARCH" = "x86_64" -o "$ARCH" = "x86" ]; then
             MACH_CFLAGS="$MACH_CFLAGS -I$HEADERS/asm-x86/mach-default"
             MACH_CFLAGS="$MACH_CFLAGS -I$SOURCES/arch/x86/include/asm/mach-default"
         fi
@@ -110,7 +110,7 @@ build_cflags() {
         fi
     else
         MACH_CFLAGS="-I$HEADERS/asm/mach-default"
-        if [ "$ARCH" = "i386" -o "$ARCH" = "x86_64" ]; then
+        if [ "$ARCH" = "i386" -o "$ARCH" = "x86_64" -o "$ARCH" = "x86" ]; then
             MACH_CFLAGS="$MACH_CFLAGS -I$HEADERS/asm-x86/mach-default"
             MACH_CFLAGS="$MACH_CFLAGS -I$SOURCES/arch/x86/include/asm/mach-default"
         fi
@@ -121,7 +121,7 @@ build_cflags() {
 
     CFLAGS="$BASE_CFLAGS $MACH_CFLAGS $OUTPUT_CFLAGS -I$HEADERS $AUTOCONF_CFLAGS"
 
-    if [ "$ARCH" = "i386" -o "$ARCH" = "x86_64" ]; then
+    if [ "$ARCH" = "i386" -o "$ARCH" = "x86_64" -o "$ARCH" = "x86" ]; then
         CFLAGS="$CFLAGS -I$SOURCES/arch/x86/include"
     fi
     if [ -n "$BUILD_PARAMS" ]; then