Added additional gsl headers

Older compilers would warn about implicit function declaration, e.g.:

gstlal_denoiser.c:240:2: warning: implicit declaration of function 'gsl_sort_vector_float_index' [-Wimplicit-function-declaration]

Newer compilers would error out.

gstlal-ugly/gst/lal/gstlal_denoiser.c

@@ -51,7 +51,9 @@
 #include <gsl/gsl_blas.h>
 #include <gsl/gsl_math.h>
 #include <gsl/gsl_permutation.h>
+#include <gsl/gsl_permute_vector.h>
 #include <gsl/gsl_sort.h>
+#include <gsl/gsl_sort_vector.h>
 #include <gsl/gsl_vector.h>