[gegl] operations/workshop/linear-sinusoid: Silence -Wmaybe-uninitialized

[Debarshi Ray <debarshir src gnome org>]

commit 7bf4d4866d82f99a6c6e23f7574f67d50a510503
Author: Debarshi Ray <debarshir gnome org>
Date:   Fri Oct 27 09:11:01 2017 +0200

    operations/workshop/linear-sinusoid: Silence -Wmaybe-uninitialized
    
    I don't know the logic to understand what the correct fix would be, so
    I am relying on the fact that zero is the additive identity and that
    these variables are used to increment other values later in the
    function.

 operations/workshop/linear-sinusoid.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/operations/workshop/linear-sinusoid.c b/operations/workshop/linear-sinusoid.c
index 221b7ae..cf10590 100644
--- a/operations/workshop/linear-sinusoid.c
+++ b/operations/workshop/linear-sinusoid.c
@@ -156,7 +156,7 @@ process (GeglOperation       *operation,
   gint            m, n;
   gdouble         u0, v0;
   gdouble         u, v;
-  gdouble         m_du, m_dv;
+  gdouble         m_du = 0.0, m_dv = 0.0;
   gdouble         n_du, n_dv;
   gfloat         *result = out_buf;