Avoid uninitialized warnings in Bessel functions.

Avoid uninitialized warnings in Bessel functions.

math/Makefile currently has:

  # The fdlibm code generates a lot of these warnings but is otherwise clean.
  override CFLAGS += -Wno-uninitialized

This is of course undesirable; warnings should be disabled as narrowly
as possible.  To remove this override, we need to fix files that
generate such warnings, or put warning-disabling pragmas in them.
This patch does so for Bessel function implementations, one of the
cases that have the warnings if the override is removed.  The warnings
arise because functions set pointer variables p and q only for certain
values of the function argument, then use them unconditionally.  As
the static functions in question only get called for arguments that
satisfy the last condition in the if/else chain, the natural fix is to
change the last "else if" to just "else", which this patch does.  (The
ldbl-128 / ldbl-128ibm implementation of these functions is
substantially different and looks like it already does use "else" in
the last case in the nearest corresponding code.)

Tested for x86_64 and x86.

	* sysdeps/ieee754/dbl-64/e_j0.c (pzero): Change last case for
	setting p and q from "else if" to "else".
	(qzero): Likewise.
	* sysdeps/ieee754/dbl-64/e_j1.c (pone): Likewise.
	(qone): Likewise.
	* sysdeps/ieee754/flt-32/e_j0f.c (pzerof): Likewise.
	(qzerof): Likewise.
	* sysdeps/ieee754/flt-32/e_j1f.c (ponef): Likewise.
	(qonef): Likewise.
	* sysdeps/ieee754/ldbl-96/e_j0l.c (pzero): Likewise.
	(qzero): Likewise.
	* sysdeps/ieee754/ldbl-96/e_j1l.c (pone): Likewise.
	(qone): Likewise.