ports: mimxrt: Fix SNVS_LP build on non-RT1176 devices.

The SDK updates includes a breaking change on devices without valid
external tamper support. This is done by adding a macro checking whether
the `FSL_FEATURE_SNVS_HAS_MULTIPLE_TAMPER` macro is defined and contains
non-zero values in SDK driver. Currently this is only enabled on RT1176,
so here we are adding the same check to prevent calling the non-exist
function on other devices.

Signed-off-by: Yilin Sun <yilin.sun@nxp.com>

ports/mimxrt/machine_rtc.c

@@ -156,8 +156,11 @@ void machine_rtc_start(void) {
     SNVS->HPCOMR |= SNVS_HPCOMR_NPSWA_EN_MASK;
     // Do a basic init.
     SNVS_LP_Init(SNVS);
+
+    #if defined(FSL_FEATURE_SNVS_HAS_MULTIPLE_TAMPER) && (FSL_FEATURE_SNVS_HAS_MULTIPLE_TAMPER > 0)
     // Disable all external Tamper
     SNVS_LP_DisableAllExternalTamper(SNVS);
+    #endif
 
     SNVS_LP_SRTC_StartTimer(SNVS);
     // If the date is not set, set it to a more recent start date,