modules: trusted-firmware-m: Update in interface implementation

Following changes to arch/arm/core/cortex_m/fpu.c,
the dependency on CONFIG_FPU_SHARING is moved into this file.

Signed-off-by: Michele Sardo <michele.sardo@st.com>

Author: msmttchr

modules/trusted-firmware-m/interface/interface.c

@@ -53,13 +53,17 @@ int32_t tfm_ns_interface_dispatch(veneer_fn fn,
 #endif
 	}
 
+#if defined(CONFIG_FPU_SHARING)
 	struct fpu_ctx_full context_buffer;
 
 	z_arm_save_fp_context(&context_buffer);
+#endif
 
 	result = fn(arg0, arg1, arg2, arg3);
 
+#if defined(CONFIG_FPU_SHARING)
 	z_arm_restore_fp_context(&context_buffer);
+#endif
 
 	if (!isr_mode) {
 #if !defined(CONFIG_ARM_NONSECURE_PREEMPTIBLE_SECURE_CALLS)