Fix building on musl libc.

src/client/linux/dump_writer_common/ucontext_reader.cc

Index: src/client/linux/dump_writer_common/ucontext_reader.cc
diff --git a/src/client/linux/dump_writer_common/ucontext_reader.cc b/src/client/linux/dump_writer_common/ucontext_reader.cc
index c80724dd878a8726a73389be27ffdc3877fdf519..668fe3c6f7cd87ebb9f025e818349fa4d79bc5cc 100644
--- a/src/client/linux/dump_writer_common/ucontext_reader.cc
+++ b/src/client/linux/dump_writer_common/ucontext_reader.cc
@@ -49,7 +49,7 @@ uintptr_t UContextReader::GetInstructionPointer(const struct ucontext* uc) {
 }
 
 void UContextReader::FillCPUContext(RawContextCPU *out, const ucontext *uc,
-                                    const struct _libc_fpstate* fp) {
+                                    const struct _fpstate* fp) {
   const greg_t* regs = uc->uc_mcontext.gregs;
 
   out->context_flags = MD_CONTEXT_X86_FULL |
@@ -97,7 +97,7 @@ uintptr_t UContextReader::GetInstructionPointer(const struct ucontext* uc) {
 }
 
 void UContextReader::FillCPUContext(RawContextCPU *out, const ucontext *uc,
-                                    const struct _libc_fpstate* fpregs) {
+                                    const struct _fpstate* fpregs) {
   const greg_t* regs = uc->uc_mcontext.gregs;
 
   out->context_flags = MD_CONTEXT_AMD64_FULL;