Update cs.c

remove a dead code, suggested by @vit9696 on #867
diff --git a/cs.c b/cs.c
index 5d0c552..afecf27 100644
--- a/cs.c
+++ b/cs.c
@@ -323,7 +323,6 @@
 #ifndef CAPSTONE_DIET
 	// fill in mnemonic & operands
 	// find first space or tab
-	sp = buffer;
 	mnem = insn->mnemonic;
 	for (sp = buffer; *sp; sp++) {
 		if (*sp == ' '|| *sp == '\t')