x86/crc: add ANNOTATE_NOENDBR to suppress objtool warnings

The assembly functions generated by crc-pclmul-template.S are called
only via static_call, so they do not need to begin with an endbr
instruction. But objtool still warns about a missing endbr by default.
Add ANNOTATE_NOENDBR to suppress these warnings:

vmlinux.o: warning: objtool: crc32_x86_init+0x1c0: relocation to !ENDBR: crc32_lsb_vpclmul_avx10_256+0x0
vmlinux.o: warning: objtool: crc64_x86_init+0x183: relocation to !ENDBR: crc64_msb_vpclmul_avx10_256+0x0
vmlinux.o: warning: objtool: crc_t10dif_x86_init+0x183: relocation to !ENDBR: crc16_msb_vpclmul_avx10_256+0x0
vmlinux.o: warning: objtool: __SCK__crc32_lsb_pclmul+0x0: data relocation to !ENDBR: crc32_lsb_pclmul_sse+0x0
vmlinux.o: warning: objtool: __SCK__crc64_lsb_pclmul+0x0: data relocation to !ENDBR: crc64_lsb_pclmul_sse+0x0
vmlinux.o: warning: objtool: __SCK__crc64_msb_pclmul+0x0: data relocation to !ENDBR: crc64_msb_pclmul_sse+0x0
vmlinux.o: warning: objtool: __SCK__crc16_msb_pclmul+0x0: data relocation to !ENDBR: crc16_msb_pclmul_sse+0x0

Fixes: 8d2d3e72e35b ("x86/crc: add "template" for [V]PCLMULQDQ based CRC functions")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Closes: https://lore.kernel.org/r/20250217170555.3d14df62@canb.auug.org.au/
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20250217193230.100443-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>