Cause whatcomp output to use the incoming epocroot value. i.e. if epocroot is relative then so is the what output.
e.g. if EPOCROOT=\ then the output will be of the form "\epoc32\release\armv5\...." If it's "..\myepocroot" then the output will be "..\myepocroot\epoc32\release\armv5". If it's absolute then the what output will also be absolute.
# romfile.mk
#
# Copyright (c) 2008 : Symbian Software Limited. All rights reserved.
#
# define macros that are needed by romfile creation
define DoRomSet
ifeq ($(call uppercase,$(TARGETTYPE)),LIB)
BUILDROMTARGET:=
endif
ifeq ($(call uppercase,$(TARGETTYPE)),KEXT)
ROMFILETYPE:=extension[MAGIC]
ABIDIR:=KMAIN
endif
ifeq ($(call uppercase,$(TARGETTYPE)),LDD)
ROMFILETYPE:=device[MAGIC]
ABIDIR:=KMAIN
endif
ifeq ($(call uppercase,$(TARGETTYPE)),PDD)
ROMFILETYPE:=device[MAGIC]
ABIDIR:=KMAIN
endif
ifeq ($(call uppercase,$(TARGETTYPE)),VAR)
ROMFILETYPE:=variant[MAGIC]
ABIDIR:=KMAIN
endif
ifeq ($(call uppercase,$(TARGETTYPE)),KDLL)
ABIDIR:=KMAIN
endif
ifneq ($(CALLDLLENTRYPOINTS),)
ROMFILETYPE:=dll
endif
ifeq ($(ROMFILETYPE),primary)
ABIDIR:=KMAIN
endif
endef