cmd/go: fix spacing in help text of -overlay flag

There was a space missing in the first line shown below, and an extra
space in the second line shown. Thanks Peter Bourgon for noting this.

BEFORE:
$ go help build | grep -A1 'has some limitations'
has some limitations:importantly, cgo files included from outside the
include path must be  in the same directory as the Go package they are

AFTER:
$ go help build | grep -A1 'has some limitations'
has some limitations: importantly, cgo files included from outside the
include path must be in the same directory as the Go package they are

Note that I edited alldocs.go by hand here, as the mkalldocs.sh script
produces a lot more changes, for example adding the -insecure flag
documentation in. Not sure what's wrong there.

Change-Id: I303f6d6b42b0e24cec0748a949dc23beec64b917
Reviewed-on: https://go-review.googlesource.com/c/go/+/319949
Reviewed-by: Jay Conrod <jayconrod@google.com>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Trust: Jay Conrod <jayconrod@google.com>
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Go Bot <gobot@golang.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/src/cmd/go/alldocs.go b/src/cmd/go/alldocs.go
index 052b61c03dd..fcc7f36335e 100644
--- a/src/cmd/go/alldocs.go
+++ b/src/cmd/go/alldocs.go
@@ -174,8 +174,8 @@
 // 		a build will run as if the disk file path exists with the contents
 // 		given by the backing file paths, or as if the disk file path does not
 // 		exist if its backing file path is empty. Support for the -overlay flag
-// 		has some limitations:importantly, cgo files included from outside the
-// 		include path must be  in the same directory as the Go package they are
+// 		has some limitations: importantly, cgo files included from outside the
+// 		include path must be in the same directory as the Go package they are
 // 		included from, and overlays will not appear when binaries and tests are
 // 		run through go run and go test respectively.
 // 	-pkgdir dir