riscv: misaligned: declare misaligned_access_speed under CONFIG_RISCV_MISALIGNED

BugLink: https://bugs.launchpad.net/bugs/2121266

[ Upstream commit 1317045a7d6f397904d105f6d40dc9787876a34b ]

While misaligned_access_speed was defined in a file compile with
CONFIG_RISCV_MISALIGNED, its definition was under
CONFIG_RISCV_SCALAR_MISALIGNED. This resulted in compilation problems
when using it in a file compiled with CONFIG_RISCV_MISALIGNED.

Move the declaration under CONFIG_RISCV_MISALIGNED so that it can be
used unconditionnally when compiled with that config and remove the check
for that variable in traps_misaligned.c.

Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>
Tested-by: Charlie Jenkins <charlie@rivosinc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20250523101932.1594077-9-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Noah Wager <noah.wager@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

Author: clementleger

arch/riscv/include/asm/cpufeature.h

@@ -71,14 +71,17 @@ bool __init check_unaligned_access_emulated_all_cpus(void);
 void check_unaligned_access_emulated(struct work_struct *work __always_unused);
 void unaligned_emulation_finish(void);
 bool unaligned_ctl_available(void);
-DECLARE_PER_CPU(long, misaligned_access_speed);
 #else
 static inline bool unaligned_ctl_available(void)
 {
 	return false;
 }
 #endif
 
+#if defined(CONFIG_RISCV_MISALIGNED)
+DECLARE_PER_CPU(long, misaligned_access_speed);
+#endif
+
 bool __init check_vector_unaligned_access_emulated_all_cpus(void);
 #if defined(CONFIG_RISCV_VECTOR_MISALIGNED)
 void check_vector_unaligned_access_emulated(struct work_struct *work __always_unused);

arch/riscv/kernel/traps_misaligned.c

@@ -368,9 +368,7 @@ static int handle_scalar_misaligned_load(struct pt_regs *regs)
 
 	perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, addr);
 
-#ifdef CONFIG_RISCV_PROBE_UNALIGNED_ACCESS
 	*this_cpu_ptr(&misaligned_access_speed) = RISCV_HWPROBE_MISALIGNED_SCALAR_EMULATED;
-#endif
 
 	if (!unaligned_enabled)
 		return -1;