clk: st: Remove uninitialized_var() usage

Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings (e.g.
"unused variable"). If the compiler thinks it is uninitialized, either
simply initialize the variable or make compiler changes. As a precursor
to removing[2] this[3] macro[4], just remove this variable since it was
actually unused:

drivers/clk/st/clkgen-fsyn.c: In function ‘quadfs_set_rate’:
drivers/clk/st/clkgen-fsyn.c:793:6: warning: unused variable ‘i’ [-Wunused-variable]
  793 |  int i;
      |      ^

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Fixes: 5f7aa9071e93 ("clk: st: Support for QUADFS inside ClockGenB/C/D/E/F")
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>

drivers/clk/st/clkgen-fsyn.c

@@ -790,7 +790,6 @@ static int quadfs_set_rate(struct clk_hw *hw, unsigned long rate,
 	struct st_clk_quadfs_fsynth *fs = to_quadfs_fsynth(hw);
 	struct stm_fs params;
 	long hwrate;
-	int uninitialized_var(i);
 
 	if (!rate || !parent_rate)
 		return -EINVAL;