firmware: qcom: scm: add a dummy qcom_scm_assign_mem()

Add a dummy qcom_scm_assign_mem() to enable building drivers when
CONFIG_COMPILE_TEST=y && CONFIG_QCOM_SCM=n.

All other qcom_scm_* functions already have a dummy version.
Signed-off-by: Niklas Cassel <niklas.cassel@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>

include/linux/qcom_scm.h

@@ -87,6 +87,10 @@ static inline int qcom_scm_pas_mem_setup(u32 peripheral, phys_addr_t addr,
 static inline int
 qcom_scm_pas_auth_and_reset(u32 peripheral) { return -ENODEV; }
 static inline int qcom_scm_pas_shutdown(u32 peripheral) { return -ENODEV; }
+static inline int qcom_scm_assign_mem(phys_addr_t mem_addr, size_t mem_sz,
+				      unsigned int *src,
+				      struct qcom_scm_vmperm *newvm,
+				      int dest_cnt) { return -ENODEV; }
 static inline void qcom_scm_cpu_power_down(u32 flags) {}
 static inline u32 qcom_scm_get_version(void) { return 0; }
 static inline u32