Since Friday -next has been failing to build various arm and arm64
configurations with:

drivers/remoteproc/qcom_common.c:210:9: error: implicit declaration of function 'kzalloc' [-Werror,-Wimplicit-function-declaration]
        info = kzalloc(sizeof(*info), GFP_KERNEL);
               ^
drivers/remoteproc/qcom_common.c:210:7: warning: incompatible integer to pointer conversion assigning to 'struct qcom_ssr_subsystem *' from 'int' [-Wint-conversion]
        info = kzalloc(sizeof(*info), GFP_KERNEL);
             ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 warning and 1 error generated.

caused by 5abfe5cf0b8358b8ad0 (remoteproc: qcom: Add per subsystem SSR
notification) which adds a use of kzalloc() without ensuring that it is
prototyped.