arch: Fix duplicates in Kconfig for parisc and sparc

Fix duplicates for sparc and parisc. This was due these following commits.

1. commit 4c97a0c8 ("arch: define CPU_BIG_ENDIAN for all fixed big
   endian archs")
2. commit 97d9f969 ("arch/sparc: Define config parameter
   CPU_BIG_ENDIAN")
3. commit 74ad3d28 ("parisc: Define CONFIG_CPU_BIG_ENDIAN")

Remove duplicates.
Signed-off-by: Babu Moger <babu.moger@oracle.com>
Signed-off-by: Helge Deller <deller@gmx.de>

arch/parisc/Kconfig

@@ -61,9 +61,6 @@ config PARISC
 config CPU_BIG_ENDIAN
 	def_bool y
 
-config CPU_BIG_ENDIAN
-	def_bool y
-
 config MMU
 	def_bool y
 

arch/sparc/Kconfig

@@ -96,9 +96,6 @@ config ARCH_PROC_KCORE_TEXT
 config CPU_BIG_ENDIAN
 	def_bool y
 
-config CPU_BIG_ENDIAN
-	def_bool y
-
 config ARCH_ATU
 	bool
 	default y if SPARC64