dtc: avoid shadowing dirname()

dirname() is declared as a function, and later on try_open() another
variable dirname is used, which shadows the dirname() function
declaration and will produce the following warnings/errors with
-Wshadow turned on:

srcpos.c: In function 'try_open':
srcpos.c:71:35: error: declaration of 'dirname' shadows a global
declaration [-Werror=shadow]
srcpos.c:37:14: error: shadowed declaration is here [-Werror=shadow]
srcpos.c: In function 'srcfile_add_search_path':
srcpos.c:183:42: error: declaration of 'dirname' shadows a global
declaration [-Werror=shadow]
srcpos.c:37:14: error: shadowed declaration is here [-Werror=shadow]
cc1: all warnings being treated as errors

Fix this by renaming the function dirname() to get_dirname().

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

srcpos.c

@@ -34,7 +34,7 @@ struct search_path {
 static struct search_path *search_path_head, **search_path_tail;
 
 
-static char *dirname(const char *path)
+static char *get_dirname(const char *path)
 {
 	const char *slash = strrchr(path, '/');
 
@@ -150,7 +150,7 @@ void srcfile_push(const char *fname)
 	srcfile = xmalloc(sizeof(*srcfile));
 
 	srcfile->f = srcfile_relative_open(fname, &srcfile->name);
-	srcfile->dir = dirname(srcfile->name);
+	srcfile->dir = get_dirname(srcfile->name);
 	srcfile->prev = current_srcfile;
 
 	srcfile->lineno = 1;