update for rocket-chip release

fsim/.gitignore

@@ -0,0 +1,18 @@
+simv*
+csrc
+*.vpd
+*.key
+DVE*
+.vcs*
+timestamp
+*.out
+*.h
+*.log
+*.cmd
+*.daidir
+*.ucli
+*.a
+*.vcd
+dramsim2_ini
+generated-src
+output