doc: fix line wrapping in buffer.markdown

Fix the line wrapping in buffer.markdown

Reviewed-By: James M Snell <jasnell@gmail.com>
PR-URL: nodejs/node-v0.x-archive#25591

doc/api/buffer.markdown

@@ -64,7 +64,9 @@ It can be constructed in a variety of ways.
 
 Allocates a new buffer of `size` octets. Note, `size` must be no more than
 [kMaxLength](smalloc.html#smalloc_smalloc_kmaxlength). Otherwise, a `RangeError`
-will be thrown here. Unlike `ArrayBuffers`, the underlying memory for buffers is not initialized. So the contents of a newly created `Buffer` is unknown. Use `buf.fill(0)`to initialize a buffer to zeroes.
+will be thrown here. Unlike `ArrayBuffers`, the underlying memory for buffers
+is not initialized. So the contents of a newly created `Buffer` is unknown.
+Use `buf.fill(0)`to initialize a buffer to zeroes.
 
 ### new Buffer(array)