libmemunreachable: fix docs formatting.

Bug: N/A
Test: gittiles
Change-Id: I59e7d22562cffa4e4a3c2a186523ae0f15623950
diff --git a/libmemunreachable/README.md b/libmemunreachable/README.md
index 6d9141a..9cc0c9b 100644
--- a/libmemunreachable/README.md
+++ b/libmemunreachable/README.md
@@ -44,7 +44,7 @@
 
 ### C++ interface ###
 
-####`bool GetUnreachableMemory(UnreachableMemoryInfo& info, size_t limit = 100)`####
+#### `bool GetUnreachableMemory(UnreachableMemoryInfo& info, size_t limit = 100)` ####
 Updates an `UnreachableMemoryInfo` object with information on leaks, including details on up to `limit` leaks.  Returns true if leak detection succeeded.
 
 #### `std::string GetUnreachableMemoryString(bool log_contents = false, size_t limit = 100)` ####