[cmake] add option for `OPENTHREAD_CONFIG_NET_DIAG_VENDOR_INFO_SET_AP…

…I_ENABLE`

This makes it easier to configure this option for testing on OTBR/RCP.

etc/cmake/options.cmake

@@ -321,6 +321,7 @@ ot_multi_option(OT_LOG_OUTPUT OT_LOG_OUTPUT_VALUES OPENTHREAD_CONFIG_LOG_OUTPUT
 
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+ot_string_option(OT_NETDIAG_VENDOR_INFO OPENTHREAD_CONFIG_NET_DIAG_VENDOR_INFO_SET_API_ENABLE "Allow setting vendor info at runtime")
 ot_string_option(OT_VENDOR_NAME OPENTHREAD_CONFIG_NET_DIAG_VENDOR_NAME "set the vendor name config")
 ot_string_option(OT_VENDOR_MODEL OPENTHREAD_CONFIG_NET_DIAG_VENDOR_MODEL "set the vendor model config")
 ot_string_option(OT_VENDOR_SW_VERSION OPENTHREAD_CONFIG_NET_DIAG_VENDOR_SW_VERSION "set the vendor sw version config")