package/openblas: fix mips64 build

Use MIPS64_GENERIC instead of SICORTEX with mips64 to avoid the
following build failure raised at least since bump to version 0.3.25 in
commit 6a172ffe6b2aa5c59427696775cfa4c189f99c19:

../kernel/mips64/amax.S:76: Error: opcode not supported on this processor: mips64 (mips64) `mtc1 $0,$f0'

MIPS64_GENERIC is available since version 0.3.22 and
https://github.com/OpenMathLib/OpenBLAS/commit/a50b29c540c25baf8f788131cc905ebe0575f253

Fixes:
 - http://autobuild.buildroot.org/results/b8da10aeb16343540ce3672faabdaa4d3bffb020
 - http://autobuild.buildroot.org/results/32702ccaa2384252058840960d8998abca294fad

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/openblas/Config.in

@@ -28,7 +28,7 @@ config BR2_PACKAGE_OPENBLAS_DEFAULT_TARGET
 	default "PPC440FP2"       if BR2_powerpc_440fp
 	# P5600 is built with MSA support which is only available in Codescape toolchains
 	default "P5600"           if BR2_mips_p5600 && BR2_TOOLCHAIN_EXTERNAL_CODESCAPE_MTI_MIPS
-	default "SICORTEX"        if BR2_MIPS_CPU_MIPS64
+	default "MIPS64_GENERIC"  if BR2_MIPS_CPU_MIPS64
 	# I6400 is built with MSA support which is only available in Codescape toolchains
 	default "I6400"           if BR2_mips_i6400 && BR2_TOOLCHAIN_EXTERNAL_CODESCAPE_IMG_MIPS
 	# OpenBLAS assumes SPARC=Sparc v9