[gnumeric] Typo.

[Morten Welinder <mortenw src gnome org>]

commit 8e75ae8fef5e1c5f9d7c49d67e9a20e1944ea2ee
Author: Morten Welinder <terra gnome org>
Date:   Tue Jul 7 21:04:56 2009 -0400

    Typo.

 plugins/plan-perfect/pln.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/plugins/plan-perfect/pln.c b/plugins/plan-perfect/pln.c
index 5a82539..512c5b2 100644
--- a/plugins/plan-perfect/pln.c
+++ b/plugins/plan-perfect/pln.c
@@ -417,7 +417,7 @@ pln_convert_expr (GnmParsePos const *pp, guint8 const *ch)
 			ch += 9 + len;
 			break;
 
-		case 31:	/* Reference to passed arguement in user defined function */
+		case 31:	/* Reference to passed argument in user defined function */
 			g_string_append (expr, "_unknown31_");
 			ch++; /* ignore arg number */
 			break;