soc/x86_64: board/x86_64/qemu_x86_64: Enable 2-processor SMP as default

We can turn this off in application code, but the default should be
SMP.

Oddball note: the SMP setting is in the soc layer and not arch, even
though I think it would be better there.  We don't actually have a
per-arch defconfig file included by kconfig.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>

boards/x86_64/qemu_x86_64/Kconfig.defconfig

@@ -6,4 +6,9 @@ config BUILD_OUTPUT_BIN
 config BOARD
 	default "qemu_x86_64"
 
+# In theory we could ask qemu for any configuration, but this seems
+# like a good default.
+config MP_NUM_CPUS
+	default 2
+
 endif # BOARD_QEMU_X86_64

soc/x86_64/x86_64/Kconfig.defconfig

@@ -6,4 +6,10 @@ config SOC
 config USE_SWITCH
 	default y
 
+# Make this the default even if we have only one CPU, mostly for test
+# coverage.  Uniprocessor apps for production purposes can get a
+# moderate code size savings by turning it off.
+config SMP
+	default y
+
 endif