[glibc/azanella/clang] riscv: Suppress clang -Wignored-attributes for feupdateenv

[Adhemerval Zanella]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=71ca6b65dc4fae08a22574bb3cd134ab710612fb

commit 71ca6b65dc4fae08a22574bb3cd134ab710612fb
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date:   Tue Apr 8 10:31:29 2025 -0300

    riscv: Suppress clang -Wignored-attributes for feupdateenv
    
    clang warns that the alias will be always resolve to
    __GI___feupdateenv even if weak definition of __GI_feupdateenv
    is overridden, which is really the intention.

Diff:
---
 sysdeps/riscv/rvf/Makefile | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/sysdeps/riscv/rvf/Makefile b/sysdeps/riscv/rvf/Makefile
new file mode 100644
index 0000000000..c58fc7887d
--- /dev/null
+++ b/sysdeps/riscv/rvf/Makefile
@@ -0,0 +1,3 @@
+ifeq ($(subdir),math))
+CFLAGS-feupdateenv.c += $(config-cflags-wno-ignored-attributes)
+endif