Fix calling eepromddtest.H

Makefile change overwrote TESTS and lost
adding of eepromddtest.H

Change-Id: I01adcc3958ce181909589b159a86a54bceb65257
Reviewed-on: http://rchgit01.rchland.ibm.com/gerrit1/82293
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Tested-by: Jenkins OP Build CI <op-jenkins+hostboot@us.ibm.com>
Tested-by: FSP CI Jenkins <fsp-CI-jenkins+hostboot@us.ibm.com>
Tested-by: Jenkins OP HW <op-hw-jenkins+hostboot@us.ibm.com>
Reviewed-by: Christian R Geddes <crgeddes@us.ibm.com>

Author: mderkse1

src/usr/i2c/test/makefile

@@ -26,7 +26,7 @@ ROOTPATH = ../../../..
 
 MODULE = testi2c
 TESTS = eepromddtest.H
-TESTS = $(if $(CONFIG_SUPPORT_EEPROM_CACHING), eecachetest.H, )
+TESTS += $(if $(CONFIG_SUPPORT_EEPROM_CACHING), eecachetest.H, )
 TESTS += i2ctest.H
 TESTS += $(if $(CONFIG_TPMDD),tpmddtest.H,)