mfd: stmpe-spi: Correct the name used in MODULE_DEVICE_TABLE

mfd: stmpe-spi: Correct the name used in MODULE_DEVICE_TABLE

The name used in the macro does not exist.

drivers/mfd/stmpe-spi.c:132:26: error: use of undeclared identifier 'stmpe_id'
  132 | MODULE_DEVICE_TABLE(spi, stmpe_id);

Fixes: e789995d5c61 ("mfd: Add support for STMPE SPI interface")
Signed-off-by: Alexey Gladkov <legion@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/79d5a847303e45a46098f2d827d3d8a249a32be3.1745591072.git.legion@kernel.org
Signed-off-by: Lee Jones <lee@kernel.org>