Use linux ephemeral range (start from 32768). More TCP debug

mongoose.h

@@ -1511,6 +1511,7 @@ extern struct mg_tcpip_driver mg_tcpip_driver_stm32;
 extern struct mg_tcpip_driver mg_tcpip_driver_w5500;
 extern struct mg_tcpip_driver mg_tcpip_driver_tm4c;
 extern struct mg_tcpip_driver mg_tcpip_driver_stm32h;
+extern struct mg_tcpip_driver mg_tcpip_driver_imxrt1020;
 
 // Drivers that require SPI, can use this SPI abstraction
 struct mg_tcpip_spi {
@@ -1529,6 +1530,21 @@ struct mg_tcpip_spi {
 #endif
 
 
+struct mg_tcpip_driver_imxrt1020_data {
+  // MDC clock divider. MDC clock is derived from IPS Bus clock (ipg_clk),
+  // must not exceed 2.5MHz. Configuration for clock range 2.36~2.50 MHz
+  //    ipg_clk       MSCR       mdc_cr VALUE
+  //    -------------------------------------
+  //                                -1  <-- tell driver to guess the value
+  //    25 MHz        0x04           0
+  //    33 MHz        0x06           1
+  //    40 MHz        0x07           2
+  //    50 MHz        0x09           3
+  //    66 MHz        0x0D           4  <-- value for iMXRT1020-EVK at max freq.
+  int mdc_cr;  // Valid values: -1, 0, 1, 2, 3, 4
+};
+
+
 struct mg_tcpip_driver_stm32_data {
   // MDC clock divider. MDC clock is derived from HCLK, must not exceed 2.5MHz
   //    HCLK range    DIVIDER    mdc_cr VALUE