sysutils/liburcu: update to 0.15.3 release (+)

What's new:

2025-05-14 Userspace RCU 0.15.3

• Fix: Use bitfield static assert with GCC < 7.1.0
• Fix: Allow compile-time checks for GCC 5.1

2025-04-14 Userspace RCU 0.15.2

• fix: __atomic_always_lock_free() not a constant expression on g++ < 5.1
• fix: urcu assert fallback for pre-C11 builds
• doc: update uatomic-api for static assert
• Add uatomic size static assert for 's390'
• Add uatomic size static assert for 'sparc64'
• Add uatomic size static assert for 'ppc'
• Add uatomic size static assert for 'x86'
• Add uatomic size static assert for 'generic'
• Add uatomic size static assert
• Use UATOMIC_HAS_ATOMIC_INT/LLONG in generic implementation
• Add UATOMIC_HAS_ATOMIC_INT/LLONG for x86
• Add UATOMIC_HAS_ATOMIC_INT/LLONG for tile
• Add UATOMIC_HAS_ATOMIC_INT/LLONG for sparc64
• Add UATOMIC_HAS_ATOMIC_INT/LLONG for s390
• Add UATOMIC_HAS_ATOMIC_INT/LLONG for riscv
• Add UATOMIC_HAS_ATOMIC_INT/LLONG for ppc
• Add UATOMIC_HAS_ATOMIC_INT/LLONG for nios2
• Add UATOMIC_HAS_ATOMIC_INT/LLONG for mips
• Add UATOMIC_HAS_ATOMIC_INT/LLONG for m68k
• Add UATOMIC_HAS_ATOMIC_INT/LLONG for loongarch
• Add UATOMIC_HAS_ATOMIC_INT/LLONG for ia64
• Add UATOMIC_HAS_ATOMIC_INT/LLONG for hppa
• Add UATOMIC_HAS_ATOMIC_INT/LLONG for 'gcc' arch
• Add UATOMIC_HAS_ATOMIC_INT/LLONG for arm
• Add UATOMIC_HAS_ATOMIC_INT/LLONG for alpha
• Add UATOMIC_HAS_ATOMIC_INT/LLONG for aarch64
• Add UATOMIC_HAS_ATOMIC_INT/LLONG for atomic builtins
• Add builtin atomics size static asserts
• cleanup: use URCU_GCC_VERSION from compiler.h
• fix: atomic builtins defines for type support
• Move back CMM_LOAD/STORE_SHARED to volatile access
• Add cmm_annotate_mem_acquire() to URCU_DEREFERENCE_USE_VOLATILE rcu_dereference
• Use uatomic_load CMM_RELAXED in URCU_DEREFERENCE_USE_VOLATILE
• Fix: Re-introduce URCU_DEREFERENCE_USE_VOLATILE read barrier depends for alpha
• Tree-wide: Rename to uatomic_load/uatomic_store
• src: Use * for attribute names
• API: Use * for attribute names
• Fix Changelog 0.15.1 date

PR: 288101
Approved by: maintainer timeout (2w)