all: fix misprints in comments

These were found by grepping the comments from the go code and feeding
the output to aspell.

Change-Id: Id734d6c8d1938ec3c36bd94a4dbbad577e3ad395
Reviewed-on: https://go-review.googlesource.com/10941
Reviewed-by: Aamir Khan <syst3m.w0rm@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/src/internal/trace/parser.go b/src/internal/trace/parser.go
index 8d48bfd..3306713 100644
--- a/src/internal/trace/parser.go
+++ b/src/internal/trace/parser.go
@@ -454,7 +454,7 @@
 			g.evStart = ev
 			p.g = ev.G
 			if g.evCreate != nil {
-				// +1 because symblizer expects return pc.
+				// +1 because symbolizer expects return pc.
 				ev.Stk = []*Frame{&Frame{PC: g.evCreate.Args[1] + 1}}
 				g.evCreate = nil
 			}
@@ -701,7 +701,7 @@
 	EvHeapAlloc      = 33 // memstats.heap_alloc change [timestamp, heap_alloc]
 	EvNextGC         = 34 // memstats.next_gc change [timestamp, next_gc]
 	EvTimerGoroutine = 35 // denotes timer goroutine [timer goroutine id]
-	EvFutileWakeup   = 36 // denotes that the revious wakeup of this goroutine was futile [timestamp]
+	EvFutileWakeup   = 36 // denotes that the previous wakeup of this goroutine was futile [timestamp]
 	EvCount          = 37
 )