ARM: OMAP2+: Stop building legacy code for dra7 and omap4/5

With the recent changes we are now booting am3/4, dra7, and omap4/5
without legacy data using devicetree, simple-pm-bus and genpd. Let's not
initialize and build the legacy data unless CONFIG_OMAP_HWMOD is selected
based on the SoCs enabled in .config.

Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap2/omap_hwmod.h

@@ -607,6 +607,8 @@ struct omap_hwmod {
 	struct omap_hwmod		*parent_hwmod;
 };
 
+#ifdef CONFIG_OMAP_HWMOD
+
 struct device_node;
 
 struct omap_hwmod *omap_hwmod_lookup(const char *name);
@@ -656,6 +658,17 @@ extern void __init omap_hwmod_init(void);
 
 const char *omap_hwmod_get_main_clk(struct omap_hwmod *oh);
 
+#else	/* CONFIG_OMAP_HWMOD */
+
+static inline int
+omap_hwmod_for_each_by_class(const char *classname,
+			     int (*fn)(struct omap_hwmod *oh, void *user),
+			     void *user)
+{
+	return 0;
+}
+#endif	/* CONFIG_OMAP_HWMOD */
+
 /*
  *
  */