dlfcn: Move dlerror into libc

The symbol was moved using scripts/move-symbol-to-libc.py.

There is a minor functionality enhancement: dlerror now sets
errno if it was set as part of the exception.  (This is the result
of using %m in asprintf, to avoid the strerror PLT call.) The
previous errno value upon function return was unpredictable.
Documenting this as a feature is premature; we need to make sure
that the error codes are meaningful when they are set by the dynamic
loader.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist

@@ -656,6 +656,7 @@ GLIBC_2.33 dirfd F
 GLIBC_2.33 dirname F
 GLIBC_2.33 div F
 GLIBC_2.33 dl_iterate_phdr F
+GLIBC_2.33 dlerror F
 GLIBC_2.33 dngettext F
 GLIBC_2.33 dprintf F
 GLIBC_2.33 drand48 F
@@ -2103,6 +2104,7 @@ GLIBC_2.34 cnd_init F
 GLIBC_2.34 cnd_signal F
 GLIBC_2.34 cnd_timedwait F
 GLIBC_2.34 cnd_wait F
+GLIBC_2.34 dlerror F
 GLIBC_2.34 execveat F
 GLIBC_2.34 mtx_destroy F
 GLIBC_2.34 mtx_init F

sysdeps/unix/sysv/linux/riscv/rv32/libdl.abilist

@@ -1,7 +1,6 @@
 GLIBC_2.33 dladdr F
 GLIBC_2.33 dladdr1 F
 GLIBC_2.33 dlclose F
-GLIBC_2.33 dlerror F
 GLIBC_2.33 dlinfo F
 GLIBC_2.33 dlmopen F
 GLIBC_2.33 dlopen F

sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist

@@ -697,6 +697,7 @@ GLIBC_2.27 dirfd F
 GLIBC_2.27 dirname F
 GLIBC_2.27 div F
 GLIBC_2.27 dl_iterate_phdr F
+GLIBC_2.27 dlerror F
 GLIBC_2.27 dngettext F
 GLIBC_2.27 dprintf F
 GLIBC_2.27 drand48 F
@@ -2303,6 +2304,7 @@ GLIBC_2.34 cnd_init F
 GLIBC_2.34 cnd_signal F
 GLIBC_2.34 cnd_timedwait F
 GLIBC_2.34 cnd_wait F
+GLIBC_2.34 dlerror F
 GLIBC_2.34 execveat F
 GLIBC_2.34 mtx_destroy F
 GLIBC_2.34 mtx_init F

sysdeps/unix/sysv/linux/riscv/rv64/libdl.abilist

@@ -1,7 +1,6 @@
 GLIBC_2.27 dladdr F
 GLIBC_2.27 dladdr1 F
 GLIBC_2.27 dlclose F
-GLIBC_2.27 dlerror F
 GLIBC_2.27 dlinfo F
 GLIBC_2.27 dlmopen F
 GLIBC_2.27 dlopen F