[S] Change in coreboot[master]: Makefiles: Drop redundant VARIANT_DIR definitions

[9elements QA (Code Review)]

9elements QA has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/74470 )

Change subject: Makefiles: Drop redundant VARIANT_DIR definitions
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Patch Set 2:

Automatic boot test returned (PASS/FAIL/TOTAL): 9 / 1 / 10

PASS: x86_32  "Hermes CFL" , build config PRODRIVE_HERMES_ 
     and payload TianoCore_UefiPayloadPkg : https://lava.9esec.io/r/159097
PASS: x86_32  "Hermes CFL" , build config PRODRIVE_HERMES 
     and payload TianoCore_UefiPayloadPkg : https://lava.9esec.io/r/159095
PASS: x86_32  "QEMU x86 q35/ich9" , build config EMULATION_QEMU_X86_Q35_SMM_TSEG 
     and payload TianoCore : https://lava.9esec.io/r/159094
PASS: x86_32  "QEMU x86 q35/ich9" , build config EMULATION_QEMU_X86_Q35_SMM_TSEG 
     and payload SeaBIOS : https://lava.9esec.io/r/159093
PASS: x86_32  "QEMU x86 q35/ich9" , build config EMULATION_QEMU_X86_Q35 
     and payload TianoCore : https://lava.9esec.io/r/159092
PASS: x86_32  "QEMU x86 q35/ich9" , build config EMULATION_QEMU_X86_Q35 
     and payload SeaBIOS : https://lava.9esec.io/r/159091
PASS: x86_64  "QEMU x86 i440fx/piix4" , build config EMULATION_QEMU_X86_I440FX_X86_64 
     and payload SeaBIOS : https://lava.9esec.io/r/159090
PASS: x86_32  "QEMU x86 i440fx/piix4" , build config EMULATION_QEMU_X86_I440FX_ASAN 
     and payload SeaBIOS : https://lava.9esec.io/r/159089
FAIL: x86_32  "QEMU x86 i440fx/piix4" , build config EMULATION_QEMU_X86_I440FX_ 
     and payload SeaBIOS : https://lava.9esec.io/r/159088
PASS: x86_32  "QEMU x86 i440fx/piix4" , build config EMULATION_QEMU_X86_I440FX 
     and payload SeaBIOS : https://lava.9esec.io/r/159087

Please note: This test is under development and might not be accurate at all!