clk: samsung: exynos-clkout: Assign .num before accessing .hws

Commit f316cdff8d67 ("clk: Annotate struct clk_hw_onecell_data with
__counted_by") annotated the hws member of 'struct clk_hw_onecell_data'
with __counted_by, which informs the bounds sanitizer (UBSAN_BOUNDS)
about the number of elements in .hws[], so that it can warn when .hws[]
is accessed out of bounds. As noted in that change, the __counted_by
member must be initialized with the number of elements before the first
array access happens, otherwise there will be a warning from each access
prior to the initialization because the number of elements is zero. This
occurs in exynos_clkout_probe() due to .num being assigned after .hws[]
has been accessed:

UBSAN: array-index-out-of-bounds in drivers/clk/samsung/clk-exynos-clkout.c:178:18
index 0 is out of range for type 'clk_hw *[*]'

Move the .num initialization to before the first access of .hws[],
clearing up the warning.

Cc: [e-mail]
Fixes: f316cdff8d67 ("clk: Annotate struct clk_hw_onecell_data with __counted_by")
Reported-by: Jochen Sprickerhof <[e-mail]>
Closes: https://lore.kernel.org/[e-mail]/
Tested-by: Jochen Sprickerhof <[e-mail]>
Signed-off-by: Nathan Chancellor <[e-mail]>
Reviewed-by: Kees Cook <[e-mail]>
Reviewed-by: Sam Protsenko <[e-mail]>
Reviewed-by: Krzysztof Kozlowski <[e-mail]>
Signed-off-by: Stephen Boyd <[e-mail]>

drivers/clk/samsung/clk-exynos-clkout.c

···
 	clkout->mux.shift = EXYNOS_CLKOUT_MUX_SHIFT;
 	clkout->mux.lock = &clkout->slock;
 
+	clkout->data.num = EXYNOS_CLKOUT_NR_CLKS;
 	clkout->data.hws[0] = clk_hw_register_composite(NULL, "clkout",
 				parent_names, parent_count, &clkout->mux.hw,
 				&clk_mux_ops, NULL, NULL, &clkout->gate.hw,
···
 		goto err_unmap;
 	}
 
-	clkout->data.num = EXYNOS_CLKOUT_NR_CLKS;
 	ret = of_clk_add_hw_provider(clkout->np, of_clk_hw_onecell_get, &clkout->data);
 	if (ret)
 		goto err_clk_unreg;