Silence some g++ compiler warnings

Changing these slightly got rid of the warnings like:
toke.c:9168: warning: format not a string literal and no format arguments

1 files changed, 1 insertions, 1 deletions

diff --git a/doio.c b/doio.c
index e915bd5c3f..08ed433d6a 100644
--- a/doio.c
+++ b/doio.c
@@ -1333,7 +1333,7 @@ I32
 Perl_my_lstat_flags(pTHX_ const U32 flags)
 {
     dVAR;
-    static const char no_prev_lstat[] = "The stat preceding -l _ wasn't an lstat";
+    static const char* const no_prev_lstat = "The stat preceding -l _ wasn't an lstat";
     dSP;
     const char *file;
     if (PL_op->op_flags & OPf_REF) {