bluetooth: services: wifi_prov: Fix setting of nanopb_BUILD_RUNTIME

`nanopb_BUILD_RUNTIME` is not an option to be passed to nanopb,
but rather a cmake one, so set it to off in the proper way.

The previous invalid form was not working as intended and only by
chance not causing any problems. With a correction that was applied
in the nanopb module (removal of leading space before the first -I
directive passed to nanopb), this behavior changed and because of
that the generation could not be performed correctly.

Signed-off-by: Andrzej Głąbek <[email protected]>

Author: anangl

subsys/bluetooth/services/wifi_prov/CMakeLists.txt

@@ -6,7 +6,7 @@
 zephyr_library()
 
 set(PROTOC_OPTIONS "-I${CMAKE_CURRENT_SOURCE_DIR}")
-set(NANOPB_OPTIONS "nanopb_BUILD_RUNTIME OFF")
+set(nanopb_BUILD_RUNTIME OFF)
 set(CMAKE_MODULE_PATH ${ZEPHYR_NANOPB_MODULE_DIR}/extra)
 find_package(Nanopb REQUIRED)
 set(NANOPB_GENERATE_CPP_STANDALONE FALSE)