Input: raydium_i2c_ts - fix error codes in raydium_i2c_boot_trigger()

These functions are supposed to return negative error codes but instead
it returns true on failure and false on success.  The error codes are
eventually propagated back to user space.

Fixes: 48a2b783

 ("Input: add Raydium I2C touchscreen driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20200303101306.4potflz7na2nn3od@kili.mountain
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>