sh_eth: factor out sh_eth_emac_interrupt()

The E-MAC interrupt (EESR.ECI) is not always caused  by an error condition,
so  it really shouldn't be handled by sh_eth_error(). Factor out the E-MAC
interrupt handler, sh_eth_emac_interrupt(),  removing the ECI bit from the
EESR's values throughout the driver...

Update Cogent Embedded's copyright and clean up the whitespace in Renesas'
copyright, while at it...

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/renesas/sh_eth.h

@@ -265,7 +265,7 @@ enum EESR_BIT {
 				 EESR_RTO)
 #define DEFAULT_EESR_ERR_CHECK	(EESR_TWB | EESR_TABT | EESR_RABT | EESR_RFE | \
 				 EESR_RDE | EESR_RFRMER | EESR_ADE | \
-				 EESR_TFE | EESR_TDE | EESR_ECI)
+				 EESR_TFE | EESR_TDE)
 
 /* EESIPR */
 enum DMAC_IM_BIT {