[Support/UNIX] posix_fallocate() can fail with EINVAL.

According to the docs on opegroup.org, the function can return
EINVAL if:

The len argument is less than zero, or the offset argument is less
than zero, or the underlying file system does not support this
operation.

I'd say it's a peculiar choice (when EONOTSUPP is right there), but
let's keep POSIX happy for now. This was independently discovered
by Mark Millard (on FreeBSD/ZFS).

Quickly ack'ed by Rui on IRC.

llvm-svn: 317535
diff --git a/llvm/lib/Support/Unix/Path.inc b/llvm/lib/Support/Unix/Path.inc
index 781a911..2ecb973 100644
--- a/llvm/lib/Support/Unix/Path.inc
+++ b/llvm/lib/Support/Unix/Path.inc
@@ -426,7 +426,7 @@
   // If we have posix_fallocate use it. Unlike ftruncate it always allocates
   // space, so we get an error if the disk is full.
   if (int Err = ::posix_fallocate(FD, 0, Size)) {
-    if (Err != EOPNOTSUPP)
+    if (Err != EINVAL && Err != EOPNOTSUPP)
       return std::error_code(Err, std::generic_category());
   }
 #endif