[musl] [PATCH] fix MINSIGSTKSZ and SIGSTKSZ for powerpc64

["psykose" <alice@ayaya.dev>]

since kernel commit 2f82ec19757f58549467db568c56e7dfff8af283
(https://github.com/torvalds/linux/commit/2f82ec19757f58549467db568c56e7dfff8af283)
the kernel has updated these minimum values. having these small values breaks
sysconf(_SC_MINSIGSTKSZ) too; it returns 4224 in musl currently which ends up
returning ENOMEM from the syscall made in sigaltstack.

raising these to match the kernel fixes sigaltstack use on powerpc64(le).
caught by glib's 2.82 testsuite
---
 arch/powerpc64/bits/signal.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc64/bits/signal.h b/arch/powerpc64/bits/signal.h
index d5493b18..3b16c4f9 100644
--- a/arch/powerpc64/bits/signal.h
+++ b/arch/powerpc64/bits/signal.h
@@ -2,8 +2,8 @@
  || defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
 
 #if defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
-#define MINSIGSTKSZ 4096
-#define SIGSTKSZ    10240
+#define MINSIGSTKSZ 8192
+#define SIGSTKSZ    32768
 #endif
 
 #if defined(_GNU_SOURCE) || defined(_BSD_SOURCE)

base-commit: dd1e63c3638d5f9afb857fccf6ce1415ca5f1b8b
-- 
2.46.0