mfd: Fix omap-usb-host build failure

The patch fixes the build failure:

drivers/mfd/omap-usb-host.c:1034:1: warning: data definition has no type
or storage class
drivers/mfd/omap-usb-host.c:1034:1: warning: type defaults to 'int' in
declaration of 'EXPORT_SYMBOL_GPL'
drivers/mfd/omap-usb-host.c:1034:1: warning: parameter names (without
types) in function declaration
drivers/mfd/omap-usb-host.c:1040:1: warning: data definition has no type
or storage class
drivers/mfd/omap-usb-host.c:1040:1: warning: type defaults to 'int' in
declaration of 'EXPORT_SYMBOL_GPL'
drivers/mfd/omap-usb-host.c:1040:1: warning: parameter names (without
types) in function declaration
drivers/mfd/omap-usb-host.c:1045:13: error: 'THIS_MODULE' undeclared
here (not in a function)
drivers/mfd/omap-usb-host.c:1050:15: error: expected declaration
specifiers or '...' before string constant
drivers/mfd/omap-usb-host.c:1050:1: warning: data definition has no type
or storage class
drivers/mfd/omap-usb-host.c:1050:1: warning: type defaults to 'int' in
declaration of 'MODULE_AUTHOR'
drivers/mfd/omap-usb-host.c:1050:15: warning: function declaration isn't
a prototype
drivers/mfd/omap-usb-host.c:1051:14: error: expected declaration
specifiers or '...' before string constant
drivers/mfd/omap-usb-host.c:1051:1: warning: data definition has no type
or storage class
drivers/mfd/omap-usb-host.c:1051:1: warning: type defaults to 'int' in
declaration of 'MODULE_ALIAS'
drivers/mfd/omap-usb-host.c:1051:14: warning: function declaration isn't
a prototype
drivers/mfd/omap-usb-host.c:1052:16: error: expected declaration
specifiers or '...' before string constant
drivers/mfd/omap-usb-host.c:1052:1: warning: data definition has no type
or storage class
drivers/mfd/omap-usb-host.c:1052:1: warning: type defaults to 'int' in
declaration of 'MODULE_LICENSE'
drivers/mfd/omap-usb-host.c:1052:16: warning: function declaration isn't
a prototype
drivers/mfd/omap-usb-host.c:1053:20: error: expected declaration
specifiers or '...' before string constant
drivers/mfd/omap-usb-host.c:1053:1: warning: data definition has no type
or storage class
drivers/mfd/omap-usb-host.c:1053:1: warning: type defaults to 'int' in
declaration of 'MODULE_DESCRIPTION'
drivers/mfd/omap-usb-host.c:1053:20: warning: function declaration isn't
a prototype
make[2]: *** [drivers/mfd/omap-usb-host.o] Error 1
  CC      fs/proc/namespaces.o
make[1]: *** [drivers/mfd] Error 2
make: *** [drivers] Error 2
make: *** Waiting for unfinished jobs....

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>