runtime: fix typos in comments

Change-Id: Ia70e8bdc6d2cf1195d7a3b5d33f180ae2db73e29
Reviewed-on: https://go-review.googlesource.com/c/go/+/305369
Reviewed-by: Emmanuel Odeke <[email protected]>
Reviewed-by: Ben Shi <[email protected]>
Run-TryBot: Emmanuel Odeke <[email protected]>
TryBot-Result: Go Bot <[email protected]>

Author: lizzzcai

src/runtime/malloc.go

@@ -933,7 +933,7 @@ func mallocgc(size uintptr, typ *_type, needzero bool) unsafe.Pointer {
 		}
 
 		if inittrace.active && inittrace.id == getg().goid {
-			// Init functions are executed sequentially in a single Go routine.
+			// Init functions are executed sequentially in a single goroutine.
 			inittrace.allocs += 1
 		}
 	}
@@ -1137,7 +1137,7 @@ func mallocgc(size uintptr, typ *_type, needzero bool) unsafe.Pointer {
 		}
 
 		if inittrace.active && inittrace.id == getg().goid {
-			// Init functions are executed sequentially in a single Go routine.
+			// Init functions are executed sequentially in a single goroutine.
 			inittrace.bytes += uint64(size)
 		}
 	}