arch: arm64: core: fpu: mark unused function argument

Use ARG_UNUSED() to mark unused function argument.

Signed-off-by: Gaetan Perrot <gaetan.perrot@spacecubics.com>

Author: moonlight83340

arch/arm64/core/fpu.c

@@ -346,6 +346,8 @@ int arch_float_disable(struct k_thread *thread)
 
 int arch_float_enable(struct k_thread *thread, unsigned int options)
 {
+	ARG_UNUSED(thread);
+	ARG_UNUSED(options);
 	/* floats always gets enabled automatically at the moment */
 	return 0;
 }