sh: remove support for sh7300 and solution engine 7300

This patch removes old dead code:
- kill off sh7300 cpu support
- get rid of broken solution engine 7300 board support

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/include/asm-sh/ubc.h b/include/asm-sh/ubc.h
index 38d46e0..56f4e30 100644
--- a/include/asm-sh/ubc.h
+++ b/include/asm-sh/ubc.h
@@ -15,8 +15,7 @@
 #include <asm/cpu/ubc.h>
 
 /* User Break Controller */
-#if defined(CONFIG_CPU_SUBTYPE_SH7707) || defined(CONFIG_CPU_SUBTYPE_SH7709) || \
-    defined(CONFIG_CPU_SUBTYPE_SH7300)
+#if defined(CONFIG_CPU_SUBTYPE_SH7707) || defined(CONFIG_CPU_SUBTYPE_SH7709)
 #define UBC_TYPE_SH7729	(current_cpu_data.type == CPU_SH7729)
 #else
 #define UBC_TYPE_SH7729	0