[Sanitizers][test] XFAIL long double tests on Solaris/sparc

As reported in Issue #41838, `clang` doesn't correctly implement `long
double` on 32-bit Solaris/SPARC: the psABI requires this to be an 128-bit
type.  Four sanitizer tests currently `FAIL` for this reason.

While there is a WIP patch to fix `clang` (D89130
<https://reviews.llvm.org/D89130>), it isn't complete yet and I've hit so
many brick walls while trying to finish it that I'm unsure if I ever will.

This patch therefore `XFAIL`s those tests in the meantime.

Tested on `sparcv9-sun-solaris2.11`.

Differential Revision: https://reviews.llvm.org/D119016

compiler-rt/test/sanitizer_common/TestCases/printf-ldbl.c

@@ -1,5 +1,8 @@
 // RUN: %clang %s -o %t && %run %t 2>&1
 
+// Issue #41838
+// XFAIL: sparc-target-arch && solaris
+
 #include <assert.h>
 #include <stdio.h>
 #include <string.h>

compiler-rt/test/sanitizer_common/TestCases/scanf-ldbl.c

@@ -1,5 +1,8 @@
 // RUN: %clang %s -o %t && %run %t 2>&1
 
+// Issue #41838
+// XFAIL: sparc-target-arch && solaris
+
 #include <assert.h>
 #include <stdio.h>
 #include <string.h>

compiler-rt/test/ubsan/TestCases/Float/cast-overflow.cpp

@@ -11,6 +11,9 @@
 // FIXME: not %run %t 8 2>&1 | FileCheck %s --check-prefix=CHECK-8
 // RUN: not %run %t 9 2>&1 | FileCheck %s --check-prefix=CHECK-9
 
+// Issue #41838
+// XFAIL: sparc-target-arch && solaris
+
 // This test assumes float and double are IEEE-754 single- and double-precision.
 
 #if defined(__APPLE__)

compiler-rt/test/ubsan/TestCases/Misc/log-path_test.cpp

@@ -25,6 +25,9 @@
 // FIXME: log_path is not supported on Windows yet.
 // XFAIL: windows-msvc
 
+// Issue #41838
+// XFAIL: sparc-target-arch && solaris
+
 #include <stdio.h>
 #include <stdlib.h>
 int main(int argc, char *argv[]) {