bugs/powerpc: Concatenate 'cond_str' with '__FILE__' in BUG_ENTRY(), to extend WARN_ON/BUG_ON output

Extend WARN_ON and BUG_ON style output from:

  WARNING: CPU: 0 PID: 0 at kernel/sched/core.c:8511 sched_init+0x20/0x410

to:

  WARNING: CPU: 0 PID: 0 at [idx < 0 && ptr] kernel/sched/core.c:8511 sched_init+0x20/0x410

Note that the output will be further reorganized later in this series.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Naveen N Rao <naveen@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: linux-arch@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Link: https://lore.kernel.org/r/20250515124644.2958810-8-mingo@kernel.org

Author: ingomolnar

arch/powerpc/include/asm/bug.h

@@ -55,7 +55,7 @@
 	__asm__ __volatile__(				\
 		"1:	" insn "\n"			\
 		_EMIT_BUG_ENTRY				\
-		: : "i" (__FILE__), "i" (__LINE__),	\
+		: : "i" (WARN_CONDITION_STR(cond_str) __FILE__), "i" (__LINE__),	\
 		  "i" (flags),				\
 		  "i" (sizeof(struct bug_entry)),	\
 		  ##__VA_ARGS__)