imximage: Encase majority of header in __ASSEMBLY__ declaration

Subsequent patches will want to include imageimage.h but in doing so
include it on an assembly compile path causing a range of compile errors.
Fix the errors pre-emptively by encasing the majority of the declarations
in imximage.h inside an ifdef __ASSEMBLY__ block.
Signed-off-by: NBryan O'Donoghue <bryan.odonoghue@linaro.org>
Cc: Utkarsh Gupta <utkarsh.gupta@nxp.com>
Cc: Breno Lima <breno.lima@nxp.com>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: NBryan O'Donoghue <bryan.odonoghue@linaro.org>
Tested-by: NBreno Lima <breno.lima@nxp.com>

include/imximage.h

@@ -56,6 +56,7 @@
 #define DCD_CHECK_BITS_SET_PARAM	0x14
 #define DCD_CHECK_BITS_CLR_PARAM	0x04
 
+#ifndef __ASSEMBLY__
 enum imximage_cmd {
 	CMD_INVALID,
 	CMD_IMAGE_VERSION,
@@ -197,4 +198,5 @@ typedef void (*set_dcd_rst_t)(struct imx_header *imxhdr,
 typedef void (*set_imx_hdr_t)(struct imx_header *imxhdr, uint32_t dcd_len,
 		uint32_t entry_point, uint32_t flash_offset);
 
+#endif /* __ASSEMBLY__ */
 #endif /* _IMXIMAGE_H_ */