Change in coreboot[master]: soc/amd/common/block: Add spi_hw mutex

[9elements QA (Code Review)]

9elements QA has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/58926 )

Change subject: soc/amd/common/block: Add spi_hw mutex
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Patch Set 3:

Automatic boot test returned (PASS/FAIL/TOTAL): 3 / 1 / 4

PASS: x86_32  "ThinkPad T500" , build config LENOVO_T500 
     and payload SeaBIOS : https://lava.9esec.io/r/82218
PASS: x86_32  "HP Z220 SFF Workstation" , build config HP_Z220_SFF_WORKSTATION 
     and payload LinuxBoot_BB_kexec : https://lava.9esec.io/r/82217
PASS: x86_32  "QEMU x86 q35/ich9" , build config EMULATION_QEMU_X86_Q35_SMM_TSEG 
     and payload SeaBIOS : https://lava.9esec.io/r/82216
FAIL: x86_32  "QEMU x86 q35/ich9" , build config EMULATION_QEMU_X86_Q35 
     and payload SeaBIOS : https://lava.9esec.io/r/82215

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