patch 9.1.1877: cindent: wrong indentation after an array declaration

patch 9.1.1877: cindent: wrong indentation after an array declaration

Problem:  cindent: wrong indentation after an array declaration
Solution: check if the filetype if javascript before matching the syntax
          (Anttoni Erkkilä)

cindent matches a javascript syntax for C files causing wrong
indentation in the following case:
```
void foo() {
float a[5],
b;
}
```

closes: #18631

Signed-off-by: Anttoni Erkkilä <anttoni.erkkila@protonmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>