clk: Initialize max_rate in struct clk_rate_request

Since commit b46fd8db ("clk: Zero the clk_rate_request structure"),
the clk_core_init_rate_req() function clears the struct clk_rate_request
passed as argument.

However, the default value for max_rate isn't 0 but ULONG_MAX, and we
end up creating a clk_rate_request instance where the maximum rate is 0.

Let's initialize max_rate to ULONG_MAX properly.

Fixes: b46fd8db

 ("clk: Zero the clk_rate_request structure")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20221018-clk-range-checks-fixes-v1-3-f3ef80518140@cerno.tech
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>