qt5webengine: only available on x86(-64) hosts

The -m32 compiler flag is used for 32bit builds and the host tools have
limited architecture support. It may work in some situations (e.g.
on aarch64 host when building a 64-bit target), but it's equally likely
that it breaks and those situations are not tested. So just limit to
x86(-64) hosts.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
[Arnout: explain that it may work in some situations]
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>

package/qt5/qt5webengine/Config.in

@@ -3,6 +3,9 @@ config BR2_PACKAGE_QT5WEBENGINE_ARCH_SUPPORTS
 	default y if BR2_aarch64 || BR2_arm || \
 		BR2_i386 || BR2_x86_64 || \
 		BR2_mips || BR2_mips64
+	# -m32 flag is used for 32bit builds and host tools have
+	# limited architecture support
+	depends on BR2_HOSTARCH = "x86_64" || BR2_HOSTARCH = "x86"
 	depends on BR2_PACKAGE_QT5_JSCORE_AVAILABLE # qt5declarative
 	depends on !BR2_BINFMT_FLAT # qt5base-icu
 	depends on BR2_USE_MMU # libglib2, qt5base-dbus