usb: r8a6659: Fix build by missing of parenthesis

By commit c7e3b2b5, this was chanded to support multiple controllers.
But this has missing of parenthesis. This commit fix it.

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r8a66597-hcd.c: In function ‘usb_lowlevel_init’:
r8a66597-hcd.c:911:52: error: expected declaration specifiers before ‘)’
token
r8a66597-hcd.c:935:1: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or‘__attribute__’ before ‘{’ token
r8a66597-hcd.c:939:1: error: expected ‘{’ at end of input
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Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
CC: Lucas Stach <dev@lynxeye.de>