[infiniband] Fix TID magic signature

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/net/infiniband/ib_mi.c

 #define IB_MI_NUM_CQES 8
 
 /** TID magic signature */
-#define IB_MI_TID_MAGIC ( ( 'g' << 24 ) | ( 'P' << 16 ) | ( 'X' << 8 ) | 'E' )
+#define IB_MI_TID_MAGIC ( ( 'i' << 24 ) | ( 'P' << 16 ) | ( 'X' << 8 ) | 'E' )
 
 /** TID to use for next MAD */
 static unsigned int next_tid;