clk: axi-clkgen: use devm_platform_ioremap_resource() short-hand

[ Upstream commit 6ba7ea7630fb03c1ce01508bdf89f5bb39b38e54 ]

No major functional change. Noticed while checking the driver code that
this could be used.
Saves two lines.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20210201151245.21845-5-alexandru.ardelean@analog.com


Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Stable-dep-of: c64ef7e4851d ("clk: clk-axi-clkgen: make sure to enable the AXI bus clock")
Signed-off-by: Sasha Levin <sashal@kernel.org>