package/azure-iot-sdk-c: needs wchar

wchar is needed since version LTS_07_2020_Ref01 which bumped internal
umock with
https://github.com/Azure/azure-iot-sdk-c/commit/8a27860452ec7345bce84d6690b0e8d167b7560a

Indeed umock unconditionally depends on wchar since
https://github.com/Azure/umock-c/commit/6b8e0160defb23ec4fde159ba6389cf61e352a0b

Fixes:
 - http://autobuild.buildroot.org/results/ad7ecd00d8f55c7cae5886c38c097ff0d071a962

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/azure-iot-sdk-c/Config.in

@@ -2,6 +2,7 @@ config BR2_PACKAGE_AZURE_IOT_SDK_C
 	bool "azure-iot-sdk-c"
 	depends on BR2_INSTALL_LIBSTDCPP
 	depends on BR2_TOOLCHAIN_HAS_THREADS_NPTL
+	depends on BR2_USE_WCHAR
 	select BR2_PACKAGE_LIBCURL
 	select BR2_PACKAGE_LIBXML2
 	select BR2_PACKAGE_OPENSSL
@@ -13,5 +14,6 @@ config BR2_PACKAGE_AZURE_IOT_SDK_C
 
 	  https://github.com/Azure/azure-iot-sdk-c
 
-comment "azure-iot-sdk-c needs a toolchain w/ C++ and NPTL"
-	depends on !BR2_INSTALL_LIBSTDCPP || !BR2_TOOLCHAIN_HAS_THREADS_NPTL
+comment "azure-iot-sdk-c needs a toolchain w/ C++, NPTL and wchar"
+	depends on !BR2_INSTALL_LIBSTDCPP || \
+		!BR2_TOOLCHAIN_HAS_THREADS_NPTL || !BR2_USE_WCHAR