exo/meso/fusee: support dynamic control of log port/baud rate

config_templates/exosphere.ini

@@ -35,6 +35,14 @@
 #    mmc space, encrypted to prevent detection. This backup can be used
 #    to prevent unrecoverable edits in emergencies.
 
+# Key: log_port, default: 0.
+#  Desc: Controls what uart port exosphere will set up for logging.
+#  NOTE: 0 = UART-A, 1 = UART-B, 2 = UART-C, 3 = UART-D
+
+# Key: log_baud_rate, default: 115200
+#  Desc: Controls the baud rate exosphere will set up for logging.
+#  NOTE: 0 is treated as equivalent to 115200.
+
 [exosphere]
 debugmode=1
 debugmode_user=0
@@ -43,3 +51,5 @@ enable_user_pmu_access=0
 blank_prodinfo_sysmmc=0
 blank_prodinfo_emummc=0
 allow_writing_to_cal_sysmmc=0
+log_port=0
+log_baud_rate=115200