Allow use of include/image.h and include/asm-*/u-boot.h in proprietary code.

The COPYING file was extended to make clear that these files can be
used in non-GPL code, too.

CHANGELOG

@@ -2,6 +2,10 @@
 Changes for U-Boot 1.1.4:
 ======================================================================
 
+* Allow use of include/image.h and include/asm-*/u-boot.h in proprietary code.
+  The COPYING file was extended to make clear that these files can be
+  used in non-GPL code, too.
+
 * Add support for Prodrive P3P440 board:
   - Added onboard PPC440 DDR autodetection in cpu/ppc/sdram.c
   - CFG_FLASH_QUIET_TEST added to use the common CFI driver

COPYING

@@ -2,10 +2,17 @@
 applications that use U-Boot services by means of the jump table
 provided by U-Boot exactly for this purpose - this is merely
 considered normal use of U-Boot, and does *not* fall under the
-heading of "derived work". Also note that the GPL below is
-copyrighted by the Free Software Foundation, but the instance of code
-that it refers to (the U-Boot source code) is copyrighted by me and
-others who actually wrote it. -- Wolfgang Denk
+heading of "derived work".
+
+  The header files "include/image.h" and "include/asm-*/u-boot.h"
+define interfaces to U-Boot. Including these (unmodified) header
+files in another file is considered normal use of U-Boot, and does
+*not* fall under the heading of "derived work".
+
+  Also note that the GPL below is copyrighted by the Free Software
+Foundation, but the instance of code that it refers to (the U-Boot
+source code) is copyrighted by me and others who actually wrote it.
+-- Wolfgang Denk
 
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