Make use of pre-existing regexp match capability to eliminate redundant

entries in template selection rules.  Also, change alpha-dec-osf pattern
to cope with version info attached to the 'alpha' part.

src/template/.similar

-alpha-dec-osf=alpha_cc
+# Format of this file is expr-style-regular-expression=templatefilename
 alpha-unknown-linux-gnu=linux_alpha
-hppa1.1-hp-hpux=hpux_cc
-hppa2.0-hp-hpux10.20=hpux_cc
+alpha[a-z0-9]*-dec-osf=alpha_cc
+arm-unknown-linux-gnu=linux_arm
+hppa[0-9.]*-hp-hpux=hpux_cc
 hppa1.1-stratus-sysv4=svr4
-i386-next-nextstep3=nextstep
-i386-pc-bsdi2.0=bsdi_2.0
-i386-pc-bsdi2.1=bsdi_2.1
-i386-pc-bsdi3=bsdi_2.1
-i386-pc-bsdi4=bsdi_4.0
-i386-pc-linux-gnu=linux_i386
-i386-pc-solaris=solaris_i386_gcc
-i386-pc-sunos5=solaris_i386_gcc
-i386-unknown-freebsd=freebsd
-i386-unknown-netbsd=netbsd
-i386-pc-cygwin32=cygwin32
-i486-pc-linux-gnu=linux_i386
-i586-pc-linux-gnu=linux_i386
-i586-pc-sco3.2v=sco
-i686-pc-linux-gnu=linux_i386
-i386-pc-cygwin=cygwin32
-i486-pc-cygwin=cygwin32
-i586-pc-cygwin=cygwin32
-i686-pc-cygwin=cygwin32
+i.86-next-nextstep3=nextstep
+i.86-pc-bsdi2.0=bsdi_2.0
+i.86-pc-bsdi2.1=bsdi_2.1
+i.86-pc-bsdi3=bsdi_2.1
+i.86-pc-bsdi4=bsdi_4.0
+i.86-pc-cygwin=cygwin32
+i.86-pc-linux-gnu=linux_i386
+i.86-pc-sco3.2v=sco
+i.86-pc-solaris=solaris_i386_gcc
+i.86-pc-sunos5=solaris_i386_gcc
+i.86-unknown-freebsd=freebsd
+i.86-unknown-netbsd=netbsd
 m68k-unknown-linux=linux_m68k
-m68k-unknown-linux-gnu=linux_m68k
+mips-pc-linux-gnu=linux_mips
 mips-sgi-irix=irix5
+mipsel-unknown-linux-gnu=linux_mips
 powerpc-ibm-aix3.2.5=aix_325
 powerpc-ibm-aix4.1=aix_41
 powerpc-ibm-aix4.2=aix_42
@@ -35,6 +30,3 @@ sparc-sun-sunos4=sunos4_gcc
 sparc-sun-sunos5=solaris_sparc_gcc
 sparc-unknown-bsdi4=bsdi_4.0_sparc
 sparc-unknown-linux-gnu=linux_sparc
-mips-pc-linux-gnu=linux_mips
-mipsel-unknown-linux-gnu=linux_mips
-arm-unknown-linux-gnu=linux_arm