west.yml: update zephyr to e4c2cecb7d8

[tmleman]

Total of 562 commits.

Changes include:

• 9cadc8cbec3 xtensa: userspace: use ADDX4 to calculate syscall table index
• 277fa9e8ac0 xtensa: userspace: swap page tables via assembly code
• 689e1121cf6 kernel: typedef k_mem_domain_t and _mem_domain_info_t
• 2abf7ce2f12 xtensa: userspace: prevent potential privilege escalation
• d5c2e4b03c8 xtensa: userspace: workaround return PC calc with loops
• bdb5723f282 xtensa: userspace: remove ununsed syscall helpers
• b0693ee41b4 xtensa: userspace: handle privileged stack in arch_cohere_stacks
• 9ebe16b6e78 xtensa: no need to restore A0/A1 if not coherence in irq exit
• 0dce0bdc0b7 xtensa: userspace: pre-compute MMU registers at domain init
• 36064939d3a xtensa: no need for flush register if threads are pin only
• 50abe899703 xtensa: userspace: use ZSR_RFI_LEVEL for userspace enter
• af5dfff3ae4 xtensa: userspace: use ZSR_RFI_LEVEL for syscall return
• 514cd384318 xtensa: userspace: remove jump to _syscall_returned
• 7f028e2f6e3 xtensa: userspace: align stack before calling syscall handler
• 482f9fbbfbc xtensa: pad IRQ stack frame to be 16 bytes aligned
• 7229b004332 xtensa: window may overflow during irq stack crossing
• 9610f1a2293 xtensa: mmu: do not force small vector table
• 774b73c8a45 xtensa: userspace: swap page table at end of cross stack call
• e0752c29380 xtensa: userspace: swap page table earlier in xtensa_switch
• 6874cdcf19f xtensa: fix unneeded cache invalidation in arch_cohere_stacks()
• 9fb87cf5864 xtensa: remove second cross stack trampoline
• 3f8e4d7400f xtensa: rework IRQ masking during IRQ entrance
• dcf75319e2a xtensa: set pointer to privileged stack only if user mode
• d725f37d5ea xtensa: userspace: calculate PC earlier at syscall entry
• 1203ed05d94 xtensa: syscall: fix setting up PS for window spilling
• 7f693679b8d xtensa: move FPU_REG_SAVE out of ODD_REG_SAVE
• c13c4995570 xtensa: add ODD_REG_RESTORE
• fc85aface12 xtensa: parameterized ODD_REG_SAVE
• 10f8882eeca xtensa: userspace: remove saving HiFi registers for syscalls
• d9f68820714 xtensa: rsync before reading ZSR_FLUSH
• a4367eb5145 xtensa: remove CONFIG_XTENSA_INVALIDATE_MEM_DOMAIN_TLB_ON_SWAP
• ee9ddb0eeba xtensa: remove CALC_PTEVADDR_BASE and PRELOAD_PTEVADDR macros
• 833bb667b2c xtensa: fix thread_page_tables_get being unused
• 71a0f39568e pm: device: correct state in pm_device_driver_init
• 226c6ae17c8 pm: Optimize pre-wakeup in suspend procedure

The current update does not point to the top of the main branch because since commit ecabcf5db56, changes have been introduced that break the compatibility of SOF's CONFIG_PM_POLICY_CUSTOM. The lost compatibility will be restored in subsequent PRs and the additional CONFIG_PM_POLICY_CUSTOM will be disabled in favor of the default version (at the moment this is not yet possible).

[kv2019i]

Thanks for the extra note on PM_POLICY_CUSTOM, this is very helpful.

[kv2019i]

Tests looking good, just waiting for more reviews.