Fix dead initialization, spotted by clang analyzer

Fix clang warnings:
/src/qemu/block/vvfat.c:1102:9: warning: Value stored to 'index3' during its initialization is never read
    int index3=index1+1;
/src/qemu/cmd.c:290:15: warning: Value stored to 'p' during its initialization is never read
        char *p = result;
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

block/vvfat.c

@@ -1099,8 +1099,8 @@ static inline void vvfat_close_current_file(BDRVVVFATState *s)
  */
 static inline int find_mapping_for_cluster_aux(BDRVVVFATState* s,int cluster_num,int index1,int index2)
 {
-    int index3=index1+1;
     while(1) {
+        int index3;
 	mapping_t* mapping;
 	index3=(index1+index2)/2;
 	mapping=array_get(&(s->mapping),index3);

cmd.c

@@ -287,7 +287,8 @@ static char *qemu_strsep(char **input, const char *delim)
 {
     char *result = *input;
     if (result != NULL) {
-        char *p = result;
+        char *p;
+
         for (p = result; *p != '\0'; p++) {
             if (strchr(delim, *p)) {
                 break;