Standardize on using __func__ instead of __FUNCTION__

The __func__ variant is standardized in C99 and recommended to be
used instead of __FUNCTION__ in the gcc info page.

Only _very_ old versions of gcc did not know about __func__, but we've
been using both __func__ and __FUNCTION__ for a long while now, and
nobody complained about this, so all our users seem to use recent
enough compilers.

Corresponding to flashrom svn r711.

Signed-off-by: Uwe Hermann <uwe@hermann-uwe.de>
Acked-by: Stefan Reinauer <stepan@coresystems.de>
diff --git a/am29f040b.c b/am29f040b.c
index 7f1269c..cde4b96 100644
--- a/am29f040b.c
+++ b/am29f040b.c
@@ -84,7 +84,7 @@
 
 	programmer_delay(10);
 
-	printf_debug("%s: id1 0x%02x, id2 0x%02x\n", __FUNCTION__, id1, id2);
+	printf_debug("%s: id1 0x%02x, id2 0x%02x\n", __func__, id1, id2);
 	if (id1 == flash->manufacture_id && id2 == flash->model_id)
 		return 1;