e1000: fix panic on large frame receive when mtu=default

A panic was reported when receiving 1522 size packets if using
the default MTU. we should set the initial rx buffer length to the
value that e1000changemtu sets so that we can receive any packet
that would not be dropped by LPE=0.

Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Auke Kok <auke.jan.h.kok@intel.com>
diff --git a/drivers/net/e1000/e1000_main.c b/drivers/net/e1000/e1000_main.c
index 0074a3a..154acb2 100644
--- a/drivers/net/e1000/e1000_main.c
+++ b/drivers/net/e1000/e1000_main.c
@@ -1068,7 +1068,7 @@
 
 	pci_read_config_word(pdev, PCI_COMMAND, &hw->pci_cmd_word);
 
-	adapter->rx_buffer_len = MAXIMUM_ETHERNET_FRAME_SIZE;
+	adapter->rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE;
 	adapter->rx_ps_bsize0 = E1000_RXBUFFER_128;
 	hw->max_frame_size = netdev->mtu +
 			     ENET_HEADER_SIZE + ETHERNET_FCS_SIZE;
@@ -3148,7 +3148,6 @@
 		adapter->rx_buffer_len = E1000_RXBUFFER_16384;
 
 	/* adjust allocation if LPE protects us, and we aren't using SBP */
-#define MAXIMUM_ETHERNET_VLAN_SIZE 1522
 	if (!adapter->hw.tbi_compatibility_on &&
 	    ((max_frame == MAXIMUM_ETHERNET_FRAME_SIZE) ||
 	     (max_frame == MAXIMUM_ETHERNET_VLAN_SIZE)))