global: Make <asm/global_data.h> include <asm/u-boot.h>

This follows the example of RISC-V where <asm/global_data.h> includes
<asm/u-boot.h> directly as "gd" includes a reference to bd_info already
and so the first must include the second anyhow. We then remove
<asm/u-boot.h> from all of the places which include references to "gd"
an so have <asm/global_data.h> already.

Signed-off-by: Tom Rini <trini@konsulko.com>

arch/xtensa/include/asm/global_data.h

@@ -6,6 +6,8 @@
 #ifndef	_XTENSA_GBL_DATA_H
 #define _XTENSA_GBL_DATA_H
 
+#include <asm/u-boot.h>
+
 /* Architecture-specific global data */
 
 struct arch_global_data {