arch/csky: fix some Kconfig typos

Fix wording in help text for the CPU_HAS_LDSTEX symbol.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Guo Ren <guoren@kernel.org>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

arch/csky/Kconfig

@@ -76,7 +76,7 @@ config CPU_HAS_TLBI
 config CPU_HAS_LDSTEX
 	bool
 	help
-	  For SMP, CPU needs "ldex&stex" instrcutions to atomic operations.
+	  For SMP, CPU needs "ldex&stex" instructions for atomic operations.
 
 config CPU_NEED_TLBSYNC
 	bool