8111C chips have bumped the mac version number. I have no
clue how the version labels in the driver are derived so I made
one up.

Reference: /n/sources/patch/applied/ether8169-newmac
Date: Thu Jul 30 02:28:06 CES 2009
Signed-off-by: lyndon@orthanc.ca

--- /sys/src/boot/pc/ether8169.c	Thu Jul 30 02:25:27 2009
+++ /sys/src/boot/pc/ether8169.c	Thu Jul 30 02:25:24 2009
@@ -111,6 +111,7 @@
 	Macv05		= 0x18000000,	/* RTL8169SC/8110SC */
 	Macv11		= 0x30000000,	/* RTL8168B/8111B */
 	Macv12		= 0x38000000,	/* RTL8169B/8111B */
+	Macv12a		= 0x3c000000,	/* RTL8169C/8111C */
 	Macv13		= 0x34000000,	/* RTL8101E */
 	Macv14		= 0x30800000,	/* RTL8100E */
 	Macv15		= 0x38800000,	/* RTL8100E */
@@ -556,6 +557,7 @@
 	case Macv04:
 	case Macv11:
 	case Macv12:
+	case Macv12a:
 	case Macv14:
 	case Macv15:
 	case Macv16:
--- /sys/src/9/pc/ether8169.c	Thu Jul 30 02:25:34 2009
+++ /sys/src/9/pc/ether8169.c	Thu Jul 30 02:25:30 2009
@@ -104,6 +104,7 @@
 	Macv05		= 0x18000000,	/* RTL8169SC/8110SC */
 	Macv11		= 0x30000000,	/* RTL8168B/8111B */
 	Macv12		= 0x38000000,	/* RTL8169B/8111B */
+	Macv12a		= 0x3c000000,	/* RTL8169C/8111C */
 	Macv13		= 0x34000000,	/* RTL8101E */
 	Macv14		= 0x30800000,	/* RTL8100E */
 	Macv15		= 0x38800000,	/* RTL8100E */
@@ -735,6 +736,7 @@
 	case Macv04:
 	case Macv11:
 	case Macv12:
+	case Macv12a:
 	case Macv14:
 	case Macv15:
 	case Macv16: