mimxrt/dma_channel: Fix the DMA channel management.

The MIMXRT1011 has only 16 channels, so size the channel list accordingly.

ports/mimxrt/dma_channel.c

@@ -27,10 +27,17 @@
 #include "dma_channel.h"
 
 // List of channel flags: true: channel used, false: channel available
-static bool channel_list[32] = { true, true, true, true, false, false, false, false,
-                                 false, false, false, false, false, false, false, false,
-                                 false, false, false, false, false, false, false, false,
-                                 false, false, false, false, false, false, false, false };
+static bool channel_list[FSL_FEATURE_DMAMUX_MODULE_CHANNEL] = {
+    true, true, true, true, false, false, false, false,
+    false, false, false, false, false, false, false, false,
+
+    #if FSL_FEATURE_DMAMUX_MODULE_CHANNEL > 16
+
+    false, false, false, false, false, false, false, false,
+    false, false, false, false, false, false, false, false
+
+    #endif
+};
 
 // allocate_channel(): retrieve an available channel. Return the number or -1
 int allocate_dma_channel(void) {