make: Disable libcxx kernel test

Disable code that requires floating point support and is linked into
the Trusty kernel as it causes builds with clang 19 and later to fail.

Bug: None
Test: Treehugger
Change-Id: I87c2aacd9f33b9987a336bc8ef1509b83634a09b

build-config-kerneltests

diff --git a/build-config-kerneltests b/build-config-kerneltests
index 832fdd6..4120ba2 100644
--- a/build-config-kerneltests
+++ b/build-config-kerneltests
@@ -24,7 +24,9 @@
     porttest("com.android.kernel.iovectest"),
     porttest("com.android.kernel.ktipc.test"),
     porttest("com.android.kernel.libctest"),
-    porttest("com.android.kernel.libcxxtest"),
+    # disabled because libcxx/libcxxabi needs floating point instructions
+    # which are not available in the kernel; clang 19 or later errors out.
+    # porttest("com.android.kernel.libcxxtest"),
     porttest("com.android.kernel.memorylatency.bench").type(BENCHMARK),
     porttest("com.android.kernel.memorytest"),
     porttest("com.android.kernel.mmutest"),

kerneltests-inc.mk

diff --git a/kerneltests-inc.mk b/kerneltests-inc.mk
index 51b3e19..9d1e421 100644
--- a/kerneltests-inc.mk
+++ b/kerneltests-inc.mk
@@ -43,7 +43,11 @@
 ifeq ($(LK_LIBC_IMPLEMENTATION),musl)
 MODULES += \
 	trusty/kernel/lib/libc-trusty/test \
-	trusty/kernel/lib/libcxx-trusty/test \
+
+# Disabled because libcxx/libcxxabi needs floating point
+# support which we don't have in the kernel so it makes
+# builds with clang 19 and later fail.
+# trusty/kernel/lib/libcxx-trusty/test \
 
 endif