icE1usb fw: Reorganize functions in e1.{c,h}

RX before TX for consistency ...

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
Change-Id: Idcb1890a3a3f4fd2129f73585c4ce9f8475f1e21
diff --git a/firmware/ice40-riscv/icE1usb/e1.h b/firmware/ice40-riscv/icE1usb/e1.h
index a93a881..a44c319 100644
--- a/firmware/ice40-riscv/icE1usb/e1.h
+++ b/firmware/ice40-riscv/icE1usb/e1.h
@@ -14,16 +14,16 @@
 void e1_poll(int port);
 void e1_debug_print(int port, bool data);
 
-void e1_tx_config(int port, uint16_t cr);
 void e1_rx_config(int port, uint16_t cr);
+void e1_tx_config(int port, uint16_t cr);
 
 
 /* data flow */
 
 unsigned int e1_rx_need_data(int port, unsigned int usb_addr, unsigned int max_len, unsigned int *pos);
 unsigned int e1_tx_feed_data(int port, unsigned int usb_addr, unsigned int len);
-unsigned int e1_tx_level(int port);
 unsigned int e1_rx_level(int port);
+unsigned int e1_tx_level(int port);
 
 
 /* error reporting */