Use unified bakery locks API in Mediatek port

This patch update Mediatek port to use the `DEFINE_BAKERY_LOCK` macro instead of
specifying the exact data structure to use for a bakery lock and the input
linker section that it should be allocated to.

Change-Id: I2116dbe27010bb46d7cc64fafef55c7240c4c721

plat/mediatek/mt8173/drivers/spm/spm.c

@@ -53,7 +53,8 @@
 static int spm_dormant_sta = CPU_DORMANT_RESET;
 #endif
 
-static bakery_lock_t spm_lock __attribute__ ((section("tzfw_coherent_mem")));
+DEFINE_BAKERY_LOCK(spm_lock);
+
 static int spm_hotplug_ready __attribute__ ((section("tzfw_coherent_mem")));
 static int spm_mcdi_ready __attribute__ ((section("tzfw_coherent_mem")));
 static int spm_suspend_ready __attribute__ ((section("tzfw_coherent_mem")));