of: of_reserved_mem: Demote kernel-doc abuses

of: of_reserved_mem: Demote kernel-doc abuses

Fixes the following W=1 kernel build warning(s):

 drivers/of/of_reserved_mem.c:53: warning: Function parameter or member 'node' not described in 'fdt_reserved_mem_save_node'
 drivers/of/of_reserved_mem.c:53: warning: Function parameter or member 'uname' not described in 'fdt_reserved_mem_save_node'
 drivers/of/of_reserved_mem.c:53: warning: Function parameter or member 'base' not described in 'fdt_reserved_mem_save_node'
 drivers/of/of_reserved_mem.c:53: warning: Function parameter or member 'size' not described in 'fdt_reserved_mem_save_node'
 drivers/of/of_reserved_mem.c:76: warning: Function parameter or member 'node' not described in '__reserved_mem_alloc_size'
 drivers/of/of_reserved_mem.c:76: warning: Function parameter or member 'uname' not described in '__reserved_mem_alloc_size'
 drivers/of/of_reserved_mem.c:76: warning: Function parameter or member 'res_base' not described in '__reserved_mem_alloc_size'
 drivers/of/of_reserved_mem.c:76: warning: Function parameter or member 'res_size' not described in '__reserved_mem_alloc_size'
 drivers/of/of_reserved_mem.c:171: warning: Function parameter or member 'rmem' not described in '__reserved_mem_init_node'

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Josh Cartwright <joshc@codeaurora.org>
Cc: devicetree@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210318104036.3175910-11-lee.jones@linaro.org