MAINTAINERS: Remove entry for Seth Heasley

Seth's mails bounce back, remove his maintainership.

Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20250505231511.3175151-1-andi.shyti@kernel.org

Author: Andi Shyti

MAINTAINERS

@@ -11235,7 +11235,6 @@ S:	Maintained
 F:	drivers/i2c/busses/i2c-cht-wc.c
 
 I2C/SMBUS ISMT DRIVER
-M:	Seth Heasley <seth.heasley@intel.com>
 M:	Neil Horman <nhorman@tuxdriver.com>
 L:	linux-i2c@vger.kernel.org
 F:	Documentation/i2c/busses/i2c-ismt.rst