Move hv_stores() declaration from embed.fnc to hv.h

This is required for the next few commits that start automatically
creating long Perl_name functions for the elements in embed.fnc that are
macros and don't already have them in the source.

Only macros can take a parameter that has to be a literal string, so
don't fit with the next few commits.  This is the only case in embed.fnc
like that, so I'm deferring dealing with it for now.

Author: khwilliamson

embed.fnc

@@ -1697,9 +1697,6 @@ Ampx	|SV **	|hv_store_flags |NULLOK HV *hv				\
 				|NULLOK SV *val 			\
 				|U32 hash				\
 				|int flags
-Admp	|SV **	|hv_stores	|NULLOK HV *hv				\
-				|"key"					\
-				|NULLOK SV *val
 Admp	|void	|hv_undef	|NULLOK HV *hv
 Xop	|void	|hv_undef_flags |NULLOK HV *hv				\
 				|U32 flags

embed.h

@@ -2294,7 +2294,6 @@
 #   define Perl_hv_store(mTHX,a,b,c,d,e)        hv_store(a,b,c,d,e)
 #   define Perl_hv_store_ent(mTHX,a,b,c,d)      hv_store_ent(a,b,c,d)
 #   define Perl_hv_store_flags(mTHX,a,b,c,d,e,f) hv_store_flags(a,b,c,d,e,f)
-#   define Perl_hv_stores(mTHX,a,b,c)           hv_stores(a,b,c)
 #   define Perl_hv_undef(mTHX,a)                hv_undef(a)
 #   define Perl_ibcmp(mTHX,a,b,c)               ibcmp(a,b,c)
 #   define Perl_ibcmp_locale(mTHX,a,b,c)        ibcmp_locale(a,b,c)
@@ -2395,7 +2394,6 @@
 #   define Perl_hv_store                        hv_store
 #   define Perl_hv_store_ent                    hv_store_ent
 #   define Perl_hv_store_flags                  hv_store_flags
-#   define Perl_hv_stores                       hv_stores
 #   define Perl_hv_undef                        hv_undef
 #   define Perl_ibcmp                           ibcmp
 #   define Perl_ibcmp_locale                    ibcmp_locale

hv.h

@@ -584,6 +584,7 @@ whether it is valid to call C<HvAUX()>.
 =for apidoc_defn Am|SV**|hv_fetchs|HV* hv|"key"|I32 lval
 =for apidoc_defn Am|SV *|hv_deletes|HV *hv|"key"|U32 flags
 =for apidoc_defn Am|void|hv_name_sets|HV *hv|"name"|U32 flags
+=for apidoc_defn Am|SV**|hv_stores|HV *hv|"name"|U32 flags
 =cut
 */
 #define hv_fetchs(hv, key, lval) \