remove a branch in SvIV_please_nomg

On VC 2003 and GCC 4.6.3, this patch decreases from 3 branches to
2 branches that machine code that makes up SvIV_please_nomg. Functionality
should be identical as before. This is intended to make math functions like
pp_add faster. Due to complexity/my time, SvIV_please wasn't optimized.
"(SvNOK(sv) || SvPOK(sv)" was optimized to
"(SvFLAGS(sv) & (SVf_NOK|SVf_POK))" on GCC and VC 2003 before this patch,
so that change reenforces what the optimizer already did before.

.text section of miniperl.exe size in bytes
gcc 32b 4.6.3 -O2 before 0x10d154
gcc 32b 4.6.3 -O2 after  0x10d064
vc2003            before 0xa4odf
vc2003            after  0xa406f

Author: bulk88

sv.h

@@ -1313,11 +1313,11 @@ sv_force_normal does nothing.
    Not guaranteed to stay returning void */
 /* Macro won't actually call sv_2iv if already IOK */
 #define SvIV_please(sv) \
-	STMT_START {if (!SvIOKp(sv) && (SvNOK(sv) || SvPOK(sv))) \
+	STMT_START {if (!SvIOKp(sv) && (SvFLAGS(sv) & (SVf_NOK|SVf_POK))) \
 		(void) SvIV(sv); } STMT_END
 #define SvIV_please_nomg(sv) \
-	(!SvIOKp(sv) && (SvNOK(sv) || SvPOK(sv)) \
-	    ? (SvIV_nomg(sv), SvIOK(sv))	  \
+	(!(SvFLAGS(sv) & (SVf_IOK|SVp_IOK)) && (SvFLAGS(sv) & (SVf_NOK|SVf_POK)) \
+	    ? (sv_2iv_flags(sv, 0), SvIOK(sv))	  \
 	    : SvIOK(sv))
 #define SvIV_set(sv, val) \
 	STMT_START { \