common/env_embedded.c: drop support for CONFIG_SYS_USE_PPCENV

CONFIG_SYS_USE_PPCENV is no longer used anywhere. It was used to put
the environment in the special .ppcenv section, but the last
architecture using this section (SuperH) has been changed to not use
it.

Therefore, this commit drops support for CONFIG_SYS_USE_PPCENV
entirely. We only handle two cases:

 - We're building the host tool tools/envcrc, in which case the
   environment is place with no special section attribute (so it
   depends up in .data)

 - We're building U-Boot itself, in which case the environnement is
   placed in the .text section.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

common/env_embedded.c

@@ -30,18 +30,11 @@
  */
 #if defined(ENV_IS_EMBEDDED) || defined(CONFIG_BUILD_ENVCRC)
 /*
- * Only put the environment in it's own section when we are building
+ * Put the environment in the .text section when we are building
  * U-Boot proper.  The host based program "tools/envcrc" does not need
- * a seperate section.  Note that ENV_CRC is only defined when building
- * U-Boot itself.
+ * a seperate section.
  */
-#if defined(CONFIG_SYS_USE_PPCENV) && \
-	defined(ENV_CRC) /* Environment embedded in U-Boot .ppcenv section */
-/* XXX - This only works with GNU C */
-#  define __PPCENV__	__attribute__ ((section(".ppcenv")))
-#  define __PPCTEXT__	__attribute__ ((section(".text")))
-
-#elif defined(USE_HOSTCC) /* Native for 'tools/envcrc' */
+#if defined(USE_HOSTCC) /* Native for 'tools/envcrc' */
 #  define __PPCENV__	/*XXX DO_NOT_DEL_THIS_COMMENT*/
 #  define __PPCTEXT__	/*XXX DO_NOT_DEL_THIS_COMMENT*/