conf/machine-sdk: declare qemu-usermode SDK_MACHINE_FEATURE

All of our defined SDK machines (which are assumed to be Linux) support
qemu-user, so state this explicitly.

(From OE-Core rev: 12f92772c8ccf622fd353836c1172e15ee8c6857)

Signed-off-by: Ross Burton <ross.burton@arm.com>
Link: https://lore.kernel.org/r/20231221170159.1995650-3-ross.burton@arm.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/conf/machine-sdk/aarch64.conf

@@ -1,2 +1,4 @@
 SDK_ARCH = "aarch64"
 ABIEXTENSION:class-nativesdk = ""
+
+SDK_MACHINE_FEATURES = "qemu-usermode"

meta/conf/machine-sdk/i586.conf

@@ -2,3 +2,4 @@ SDK_ARCH = "i586"
 SDK_CC_ARCH = "-march=i586"
 ABIEXTENSION:class-nativesdk = ""
 
+SDK_MACHINE_FEATURES = "qemu-usermode"

meta/conf/machine-sdk/i686.conf

@@ -1,3 +1,5 @@
 SDK_ARCH = "i686"
 SDK_CC_ARCH = "-march=i686"
 ABIEXTENSION:class-nativesdk = ""
+
+SDK_MACHINE_FEATURES = "qemu-usermode"

meta/conf/machine-sdk/loongarch64.conf

@@ -1,2 +1,4 @@
 SDK_ARCH = "loongarch64"
 ABIEXTENSION:class-nativesdk = ""
+
+SDK_MACHINE_FEATURES = "qemu-usermode"

meta/conf/machine-sdk/ppc64.conf

@@ -1,2 +1,4 @@
 SDK_ARCH = "ppc64"
 ABIEXTENSION:class-nativesdk = ""
+
+SDK_MACHINE_FEATURES = "qemu-usermode"

meta/conf/machine-sdk/ppc64le.conf

@@ -1,2 +1,4 @@
 SDK_ARCH = "ppc64le"
 ABIEXTENSION:class-nativesdk = ""
+
+SDK_MACHINE_FEATURES = "qemu-usermode"

meta/conf/machine-sdk/riscv64.conf

@@ -1,2 +1,4 @@
 SDK_ARCH = "riscv64"
 ABIEXTENSION:class-nativesdk = ""
+
+SDK_MACHINE_FEATURES = "qemu-usermode"

meta/conf/machine-sdk/x86_64.conf

@@ -2,3 +2,5 @@ SDK_ARCH = "x86_64"
 SDK_CC_ARCH = "-march=x86-64"
 ABIEXTENSION:class-crosssdk = ""
 ABIEXTENSION:class-nativesdk = ""
+
+SDK_MACHINE_FEATURES = "qemu-usermode"